The West Nile Virus Guide
&
Mosquito Fact Book
Compiled, edited & published by Scott Parat
A Culex quinquefasciatus mosqui...
West Nile Virus --- Facts, Resources & Information
I dedicate this book to my loving wife who has endured my
hours of rese...
West Nile Virus --- Facts, Resources & Information
With the advent of west nile virus, my wife and I became
concerned for ...
West Nile Virus --- Facts, Resources & Information
PREFACE...................................................................
West Nile Virus --- Facts, Resources & Information
QUESTIONS AND ANSWERS ABOUT MOSQUITO PREVENTION FOR PEOPLE, PROPERTY
AN...
West Nile Virus --- Facts, Resources & Information
WEST NILE VIRUS, PREGNANCY AND BREAST-FEEDING.............................
West Nile Virus --- Facts, Resources & Information
Introduction to the West Nile Virus
West Nile virus emerged in the Unit...
West Nile Virus --- Facts, Resources & Information
West Nile Virus Guide
-------------------------------------------------...
West Nile Virus --- Facts, Resources & Information
Background: Virus History and Distribution
Introduction
West Nile virus...
West Nile Virus --- Facts, Resources & Information
• Human case information and maps from 2002
• From 1999 through 2001, t...
West Nile Virus --- Facts, Resources & Information
• Infected Mosquitoes. Most often, WNV is spread by the bite of an infe...
West Nile Virus --- Facts, Resources & Information
Administration and other government agencies, as well as private indust...
West Nile Virus --- Facts, Resources & Information
Links to State and Local Government West Nile
Virus Web Sites
Click on ...
West Nile Virus --- Facts, Resources & Information
• Illinois
• Indiana
• Iowa
• Kansas
• Kentucky
• Louisiana
• Maine
• M...
West Nile Virus --- Facts, Resources & Information
Add
West Nile Virus Guide
---------------------------------------------...
West Nile Virus --- Facts, Resources & Information
It's time to prepare for West Nile Virus.
West Nile Virus is spread by ...
West Nile Virus --- Facts, Resources & Information
• It is always a good idea for children to avoid mosquito bites, but it...
West Nile Virus --- Facts, Resources & Information
West Nile Virus Transmission Cycle
• Horses infected with West Nile Vir...
West Nile Virus --- Facts, Resources & Information
Add
West Nile Virus Guide
---------------------------------------------...
West Nile Virus --- Facts, Resources & Information
Fight The Bite!
Avoid Mosquito Bites to Avoid Infection
Fight The Bite!...
West Nile Virus --- Facts, Resources & Information
Mosquito-Proof Your Home
Drain standing water
from around your
home
Dra...
West Nile Virus --- Facts, Resources & Information
and repellents is the National Pesticide Information Center, which also...
West Nile Virus --- Facts, Resources & Information
these active ingredients typically provide longer-lasting protection th...
West Nile Virus --- Facts, Resources & Information
• Even if you’re going out for 10 minutes use a repellent —that’s long ...
West Nile Virus --- Facts, Resources & Information
a separate sunscreen. No data are available at this time regarding the ...
West Nile Virus --- Facts, Resources & Information
use. Permethrin is highly effective as an insecticide and as a repellen...
West Nile Virus --- Facts, Resources & Information
Vertebrate Ecology
Transmission Cycle
West Nile (WN) virus is amplified...
West Nile Virus --- Facts, Resources & Information
There is no reason to destroy an animal just because it has been infect...
West Nile Virus --- Facts, Resources & Information
In the United States, West Nile virus is transmitted by infected mosqui...
West Nile Virus --- Facts, Resources & Information
microscope. Therefore, images of West Nile virus are representative for...
West Nile Virus --- Facts, Resources & Information
should take care to identify the individuals, organizations, and agenci...
West Nile Virus --- Facts, Resources & Information
• Support mosquito control activities
Report mosquito breeding sites un...
West Nile Virus --- Facts, Resources & Information
Mosquitoes
Each summer, hordes of these insects descend on backyards, p...
West Nile Virus --- Facts, Resources & Information
Although difficult to treat, the disease is easily prevented by medicat...
West Nile Virus --- Facts, Resources & Information
• Empty plastic wading pools at least once a week and store indoors whe...
West Nile Virus --- Facts, Resources & Information
to exposed skin if label permits. Consult a physician before using repe...
West Nile Virus --- Facts, Resources & Information
• Repair leaky pipes and outside faucets.
• Empty plastic wading pools ...
West Nile Virus --- Facts, Resources & Information
Questions and Answers about Mosquito
Prevention for People, Property an...
West Nile Virus --- Facts, Resources & Information
overlook containers that
have become overgrown
by vegetation.
• At leas...
West Nile Virus --- Facts, Resources & Information
• Be sure door and window screens are tight-fitting and in good repair....
West Nile Virus --- Facts, Resources & Information
double plastic bags to place carcasses in a garbage can. After disposin...
Westnile virus book2
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Westnile virus book2

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West Nile
Vir
u
s
--
- Facts,
Res
o
u
r
ces & In
fo
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m
ation
Introduction to the W
est Nile V
i
rus
We
st Nile virus eme
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g
ed i
n
the United
States in the Ne
w York me
tropolitan a
r
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a
in the fall of
1999. Since then, the virus,
whi
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h can be
transmitted to human
s by
the bite of an infected mo
squito, has
quickly sp
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across the
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Westnile virus book2

  1. 1. The West Nile Virus Guide & Mosquito Fact Book Compiled, edited & published by Scott Parat A Culex quinquefasciatus mosquito on a human finger. The Culex quinquefasciatus mosquito is proven to be a vector associated with transmission of the West Nile Virus.
  2. 2. West Nile Virus --- Facts, Resources & Information I dedicate this book to my loving wife who has endured my hours of research and constant attempts to publish this book. A book that I hope makes information regarding the west nile virus available in a concise, life changing form. You’ve endured my constant illness and have stood by. I am indeed a blessed man. Liz, I love you! Preface I want to “thank-you” for purchasing the “West Nile Virus Guide” and hope that you’ll find it very practical and useful. My goal was to provide you with information that you need to realize that the west nile virus is a real threat and I wanted to provide you with the information you need to protect yourself and loved ones from possibly contracting this dangerous disease. If you register your copy of this ebook, I’ll keep you informed of updates, new resources and new developments pertaining to west nile virus and mosquito control. Send a blank email to westnilevirus_guide-28@best-e-book.com and you’ll be automatically registered. Anytime you see blue text with a line under it, chances are that it is a hyper-link, that means if you place your mouse pointer over it, you’ll be able to click on that link and if you are connected to the internet, you’ll go straight to that website. At the time of publishing this ebook all links were active. I cannot control links that belong to other people so please don’t send me an email regarding a link that’s not working… I simply can’t do anything about it. I struggled with writing an appropriate introduction to a book that is so close to my heart. So I decided to approach the chore from a practical point of view. I happen to live in a low lying area in Midwestern United States. I have a river on one end of my property and a conservation area on the other end..this area floods every spring and holds 2 to 3 feet of water. It becomes a virtual “mosquito factory”! West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 2 -
  3. 3. West Nile Virus --- Facts, Resources & Information With the advent of west nile virus, my wife and I became concerned for the health of our family. During the summer months you can literally hear the buzz sound of mosquitoes as twilight approaches. It’s currently early fall and you won’t believe this but I’m watching 2 mosquitoes hover around my desklamp. Yep, they invade the house everytime the door is open. By now you must be getting the picture. Mosquitoes plus west nile virus was a reality in our lives. It’s September and as I listen to the radio another elderly man, 78 just died from a west nile virus infection. It’s real..it’s here and you need to protect yourself. As you read you’ll find out that the virus is traveling across the United States. If it’s not in your state now..it will be! The west nile virus is not restricted to the United States. As I studied, I discovered the virus has affected much of the world. This particular book covers issues in the United States, however, the facts regarding to the virus and mosquitoes can be applied to anyplace the virus and mosquitoes are present. I hope and pray that you, your family and loved ones will be positively affected by the knowledge you gain from reading this ebook and applying the facts. To your health, Scott Parat ========================= Note: The below Table of Contents is live. You can click on either a description or page number and be taken to that page. It is a very easy way to navigate and use this book as a reference guide. This book was compiled from different US governmental agencies and is based on current research regarding the west nile virus and mosquito and their respective control. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 3 -
  4. 4. West Nile Virus --- Facts, Resources & Information PREFACE..................................................................................................................................................... 2 INTRODUCTION TO THE WEST NILE VIRUS ................................................................................... 7 BACKGROUND: VIRUS HISTORY AND DISTRIBUTION................................................................. 9 HISTORY..................................................................................................................................................... 9 HUMAN CASE AND VIRUS DISTRIBUTION INFORMATION............................................................................ 9 WEST NILE VIRUS: WHAT YOU NEED TO KNOW......................................................................... 10 WHAT IS WEST NILE VIRUS? ................................................................................................................... 10 WHAT CAN I DO TO PREVENT WNV?...................................................................................................... 10 WHAT ARE THE SYMPTOMS OF WNV?..................................................................................................... 10 HOW DOES WEST NILE VIRUS SPREAD? .................................................................................................. 10 HOW SOON DO INFECTED PEOPLE GET SICK?.......................................................................................... 11 HOW IS WNV INFECTION TREATED? ....................................................................................................... 11 WHAT SHOULD I DO IF I THINK I HAVE WNV? ....................................................................................... 11 WHAT IS THE RISK OF GETTING SICK FROM WNV? ................................................................................. 11 WHAT ELSE SHOULD I KNOW?................................................................................................................. 12 LINKS TO STATE AND LOCAL GOVERNMENT WEST NILE VIRUS WEB SITES................... 13 LIST OF STATE AND LOCAL HEALTH DEPARTMENT WEB SITES, BY STATE AND CITY HEALTH DEPARTMENT WEST NILE VIRUS WEB SITES ........................................................................................... 13 ADD.......................................................................................................................................................... 15 IT'S TIME TO PREPARE FOR WEST NILE VIRUS. ......................................................................... 16 FIVE COMMON MYTHS ABOUT WEST NILE VIRUS.................................................................................... 16 WEST NILE VIRUS TRANSMISSION CYCLE................................................................................................ 18 WHAT YOU NEED TO KNOW ABOUT MOSQUITO REPELLENT ............................................... 22 WHICH MOSQUITO REPELLENTS WORK BEST .......................................................................................... 22 UPDATED INFORMATION REGARDING INSECT REPELLENTS...................................................................... 25 VERTEBRATE ECOLOGY ..................................................................................................................... 27 BIRDS ....................................................................................................................................................... 27 DOGS AND CATS....................................................................................................................................... 27 HORSES .................................................................................................................................................... 28 OTHER VERTEBRATES .............................................................................................................................. 28 ENTOMOLOGY........................................................................................................................................ 28 VIROLOGY: CLASSIFICATION OF WEST NILE VIRUS ................................................................................. 29 PUBLIC HEALTH CONFRONTS THE MOSQUITO: DEVELOPING SUSTAINABLE STATE AND LOCAL MOSQUITO CONTROL PROGRAMS............................................................................................................................... 30 WHAT YOU CAN DO ABOUT MOSQUITO CONTROL.................................................................................. 31 MOSQUITOES........................................................................................................................................... 33 WHAT KINDS OF MOSQUITOES ARE COMMON IN ILLINOIS? ....................................................................... 33 DO ALL MOSQUITOES CARRY DISEASE? .................................................................................................... 33 WHAT IS THE BEST WAY TO REDUCE POPULATIONS OF MOSQUITOES? ...................................................... 34 HOW CAN PEOPLE PROTECT THEMSELVES FROM MOSQUITO BITES?.......................................................... 35 MOSQUITOES AND ENCEPHALITIS.................................................................................................. 36 DISEASES.................................................................................................................................................. 36 PREVENT MOSQUITOES FROM BREEDING AROUND THE HOME................................................................. 36 West Nile Virus Guide PROTECTION FROM MOSQUITO BITES....................................................................................................... 37 ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 4 -
  5. 5. West Nile Virus --- Facts, Resources & Information QUESTIONS AND ANSWERS ABOUT MOSQUITO PREVENTION FOR PEOPLE, PROPERTY AND PETS .................................................................................................................................................. 38 WHAT KINDS OF DISEASES CAN BE CARRIED BY MOSQUITOES?................................................................. 38 WHAT IS ENCEPHALITIS? .......................................................................................................................... 38 HOW CAN I HELP PROTECT MY FAMILY AND MYSELF FROM MOSQUITOES AND THE DISEASES THEY MAY CARRY? .................................................................................................................................................... 38 QUESTIONS AND ANSWERS ABOUT SPRAYING FOR ADULT MOSQUITOES ...................... 41 WHAT INSECTICIDES ARE USED TO FOG FOR MOSQUITOES? ...................................................................... 42 ARE THE INSECTICIDES USED FOR FOGGING SAFE?.................................................................................... 43 DO I NEED TO WASH HOME-GROWN FRUITS AND VEGETABLES AFTER THE MOSQUITO FOGGING?............. 43 WILL THE FOGGING KILL BIRDS OR OTHER LARGE ANIMALS? ................................................................... 44 THE EPA, PESTICIDES AND MOSQUITO CONTROL..................................................................... 45 HOW ARE MOSQUITOES CONTROLLED WITH PESTICIDES AND OTHER METHODS?................................... 46 WHAT CAN I DO TO REDUCE THE NUMBER OF MOSQUITOES IN AND AROUND MY HOME?..................... 46 THE EPA’S VIEW OF LARVICIDES FOR MOSQUITO CONTROL................................................................... 48 WHAT IS THE MOSQUITO LIFE CYCLE? .................................................................................................... 49 WHAT ARE LARVICIDES?.......................................................................................................................... 49 WHAT ARE MICROBIAL LARVICIDES? ...................................................................................................... 49 INFORMATION ON ARBOVIRAL ENCEPHALITIDES.................................................................... 53 LA CROSSE ENCEPHALITIS ....................................................................................................................... 55 EASTERN EQUINE ENCEPHALITIS.............................................................................................................. 56 WESTERN EQUINE ENCEPHALITIS............................................................................................................. 56 ST. LOUIS ENCEPHALITIS.......................................................................................................................... 57 POWASSAN ENCEPHALITIS ....................................................................................................................... 57 VENEZUELAN EQUINE ENCEPHALITIS....................................................................................................... 57 JAPANESE ENCEPHALITIS.......................................................................................................................... 58 TICK-BORNE ENCEPHALITIS..................................................................................................................... 58 WEST NILE ENCEPHALITIS ....................................................................................................................... 59 QUESTIONS AND ANSWERS ABOUT WEST NILE .......................................................................... 60 OVERVIEW OF WEST NILE VIRUS .................................................................................................... 61 CASES OF WEST NILE HUMAN DISEASE ................................................................................................... 62 UNDERSTANDING THE NUMBERS POSTED FOR WEST NILE VIRUS CASES........................................ 63 WEST NILE VIRUS AND DEAD BIRDS ............................................................................................... 65 WHO'S AT RISK FOR WEST NILE VIRUS ......................................................................................... 65 TRANSMISSION ....................................................................................................................................... 66 WEST NILE VIRUS POLIOMYELITIS ....................................................................................................... 71 PREVENTION............................................................................................................................................. 72 INSECT REPELLENT USE AND SAFETY........................................................................................... 74 GENERAL QUESTIONS............................................................................................................................... 74 ACTIVE INGREDIENTS (TYPES OF INSECT REPELLENT)............................................................................. 74 USING REPELLENTS PROPERLY ................................................................................................................ 76 CHILDREN ................................................................................................................................................ 77 INSECT REPELLENTS CONTAINING DEET AND SUNSCREEN...................................................................... 78 WEST NILE VIRUS VACCINE...................................................................................................................... 79 TESTING AND TREATING WEST NILE VIRUS IN HUMANS UPDATED!................................ 80 QUESTIONS ABOUT COMMERCIAL LABORATORIES................................................................. 81 West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 5 -
  6. 6. West Nile Virus --- Facts, Resources & Information WEST NILE VIRUS, PREGNANCY AND BREAST-FEEDING......................................................... 82 BREASTFEEDING....................................................................................................................................... 84 BLOOD TRANSFUSION, ORGAN DONATION AND BLOOD DONATION SCREENING INFORMATION .............. 85 UPDATE ON DETECTION OF WNV IN BLOOD DONATIONS -- FROM MMWR, SEPTEMBER 18, 2003........................................................................................................................................................ 85 GENERAL INFORMATION ON SCREENING OF BLOOD DONATIONS FOR WNV ................. 86 PESTICIDES USED IN MOSQUITO CONTROL................................................................................. 91 WEST NILE VIRUS AND DOGS AND CATS ....................................................................................... 93 WEST NILE VIRUS AND HORSES........................................................................................................ 94 WEST NILE VIRUS AND SQUIRRELS .......................................................................................................... 95 WEST NILE VIRUS AND WILD GAME/MEAT ............................................................................................. 96 RECOMMENDATIONS FOR PROTECTING OUTDOOR WORKERS FROM WEST NILE VIRUS EXPOSURE................................................................................................................................. 103 Recommendations for employers of Outdoor Workers ..................................................................... 103 RECOMMENDATIONS FOR WORKERS....................................................................................................... 104 RECOMMENDATIONS FOR PROTECTING LABORATORY, FIELD, AND CLINICAL WORKERS FROM WEST NILE VIRUS EXPOSURE....................................................................... 105 Occupational Risk............................................................................................................................. 105 Recommendations for employers ...................................................................................................... 106 Recommendations for workers.......................................................................................................... 106 .......................................................................................................................................... 107CONCLUSION West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 6 -
  7. 7. West Nile Virus --- Facts, Resources & Information Introduction to the West Nile Virus West Nile virus emerged in the United States in the New York metropolitan area in the fall of 1999. Since then, the virus, which can be transmitted to humans by the bite of an infected mosquito, has quickly spread across the country. In Illinois, West Nile virus was first identified in September 2001 when laboratory tests confirmed its presence in two dead crows found in the Chicago area. The following year, the state's first human cases and deaths from West Nile disease were recorded and all but two of the state's 102 counties eventually reported a positive human, bird, mosquito or horse case. By the end of 2002, Illinois had counted more human cases (884) and deaths (67) than any other state in the nation. In 2003, the epicenter of West Nile disease moved westward. Colorado reported the highest number of cases (2,947), easily surpassing the caseload record for the mosquito-borne disease set the previous year by Illinois. The number of West Nile human cases in Illinois fell dramatically with just 54 reported and only one death. Illinois' caseload in 2004 was slightly higher than the previous year with 60 reported cases and four deaths. For the second consecutive year, the country's western states had the most cases with California leading the way with 771, followed by Arizona with 391 and Colorado with 276. In 2005, Illinois' first human cases were reported on July 29. Most state Public Health services maintain a sophisticated disease surveillance system to monitor animals and insects that can potentially carry the virus: dead crows, robins, blue jays, mosquitoes and horses. Mosquitoes can either carry the virus or get it by feeding on infected birds. The surveillance system also includes infectious disease physicians, hospital laboratory directors and infection control practitioners, local health departments and laboratory staff, environmental health and infectious diseases divisions who test for and report suspect or confirmed cases of various diseases that can be caused by mosquito-borne viruses. Mild cases of West Nile infections may cause a slight fever or headache. More severe infections are marked by a rapid onset of a high fever with head and body aches, disorientation, tremors, convulsions and, in the most severe cases, paralysis or death. Usually symptoms occur from three to 14 days after the bite of an infected mosquito. Persons at the highest risk for serious illness are those 50 years of age or older. The best way to prevent West Nile encephalitis and other mosquito-borne illnesses is to reduce the number of mosquitoes around your home and neighborhood and to take personal precautions to avoid mosquito bites. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 7 -
  8. 8. West Nile Virus --- Facts, Resources & Information West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 8 -
  9. 9. West Nile Virus --- Facts, Resources & Information Background: Virus History and Distribution Introduction West Nile virus (WNV) has emerged in recent years in temperate regions of Europe and North America, presenting a threat to public and animal health. The most serious manifestation of WNV infection is fatal encephalitis (inflammation of the brain) in humans and horses, as well as mortality in certain domestic and wild birds. WNV has also been a significant cause of human illness in the United States in 2002 and 2003. West Nile Virus Guide History West Nile virus was first isolated from a febrile adult woman in the West Nile District of Uganda in 1937. The ecology was characterized in Egypt in the 1950s. The virus became recognized as a cause of severe human meningitis or encephalitis (inflammation of the spinal cord and brain) in elderly patients during an outbreak in Israel in 1957. Equine disease was first noted in Egypt and France in the early 1960s. WNV first appeared in North America in 1999, with encephalitis reported in humans and horses.The subsequent spread in the United States is an important milestone in the evolving history of this virus. View enlarged map of laboratory-positive West Nile virus infections during 2003 Geographic Distribution West Nile virus has been described in Africa, Europe, the Middle East, west and central Asia, Oceania (subtype Kunjin), and most recently, North America. Outbreaks of WNV encephalitis in humans have occurred in Algeria in 1994, Romania in 1996-1997, the Czech Republic in 1997, the Democratic Republic of the Congo in 1998, Russia in 1999, the United States in 1999-2003, and Israel in 2000. Epizootics of disease in horses occurred in Morocco in 1996, Italy in 1998, the United States in 1999-2001, and France in 2000, and in birds in Israel in 1997-2001 and in the United States in 1999-2002. In the U.S. since 1999, WNV human, bird, veterinary or mosquito activity have been reported from all states except Hawaii, Alaska, and Oregon. Human Case and Virus Distribution Information • Current human case and epizootic distribution maps (on Statistics, Surveillance, and Control page) • Case human counts for 2003 ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 9 -
  10. 10. West Nile Virus --- Facts, Resources & Information • Human case information and maps from 2002 • From 1999 through 2001, there were 149 cases of West Nile virus human illness in the United States reported to CDC and confirmed, including 18 deaths. West Nile Virus: What You Need To Know What Is West Nile Virus? West Nile virus (WNV) is a potentially serious illness. Experts believe WNV is established as a seasonal epidemic in North America that flares up in the summer and continues into the fall. This fact sheet contains important information that can help you recognize and prevent West Nile virus. What Can I Do to Prevent WNV? The easiest and best way to avoid WNV is to prevent mosquito bites. • When you are outdoors, use insect repellent containing an EPA-registered active ingredient. Follow the directions on the package. • Many mosquitoes are most active at dusk and dawn. Be sure to use insect repellent and wear long sleeves and pants at these times or consider staying indoors during these hours. • Make sure you have good screens on your windows and doors to keep mosquitoes out. • Get rid of mosquito breeding sites by emptying standing water from flower pots, buckets and barrels. Change the water in pet dishes and replace the water in bird baths weekly. Drill holes in tire swings so water drains out. Keep children's wading pools empty and on their sides when they aren't being used. What Are the Symptoms of WNV? • Serious Symptoms in a Few People. About one in 150 people infected with WNV will develop severe illness. The severe symptoms can include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. These symptoms may last several weeks, and neurological effects may be permanent. • Milder Symptoms in Some People. Up to 20 percent of the people who become infected have symptoms such as fever, headache, and body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach and back. Symptoms can last for as short as a few days, though even healthy people have become sick for several weeks. • No Symptoms in Most People. Approximately 80 percent of people (about 4 out of 5) who are infected with WNV will not show any symptoms at all. How Does West Nile Virus Spread? West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 10 -
  11. 11. West Nile Virus --- Facts, Resources & Information • Infected Mosquitoes. Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite. West Nile Virus Guide • Transfusions, Transplants, and Mother-to-Child. In a very small number of cases, WNV also has been spread through blood transfusions, organ transplants, breastfeeding and even during pregnancy from mother to baby. • Not through touching. WNV is not spread through casual contact such as touching or kissing a person with the virus. How Soon Do Infected People Get Sick? People typically develop symptoms between 3 and 14 days after they are bitten by the infected mosquito. How Is WNV Infection Treated? There is no specific treatment for WNV infection. In cases with milder symptoms, people experience symptoms such as fever and aches that pass on their own, although even healthy people have become sick for several weeks. In more severe cases, people usually need to go to the hospital where they can receive supportive treatment including intravenous fluids, help with breathing and nursing care. What Should I Do if I Think I Have WNV? Milder WNV illness improves on its own, and people do not necessarily need to seek medical attention for this infection though they may choose to do so. If you develop symptoms of severe WNV illness, such as unusually severe headaches or confusion, seek medical attention immediately. Severe WNV illness usually requires hospitalization. Pregnant women and nursing mothers are encouraged to talk to their doctor if they develop symptoms that could be WNV. What Is the Risk of Getting Sick from WNV? People over 50 at higher risk to get severe illness. People over the age of 50 are more likely to develop serious symptoms of WNV if they do get sick and should take special care to avoid mosquito bites. Being outside means you're at risk. The more time you're outdoors, the more time you could be bitten by an infected mosquito. Pay attention to avoiding mosquito bites if you spend a lot of time outside, either working or playing. Risk through medical procedures is very low. All donated blood is checked for WNV before being used. The risk of getting WNV through blood transfusions and organ transplants is very small, and should not prevent people who need surgery from having it. If you have concerns, talk to your doctor. Pregnancy and nursing do not increase risk of becoming infected with WNV. The risk that WNV may present to a fetus or an infant infected through breastmilk is still being evaluated. Talk with your care provider if you have concerns. What Is the CDC Doing About WNV? CDC is working with state and local health departments, the Food and Drug ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 11 -
  12. 12. West Nile Virus --- Facts, Resources & Information Administration and other government agencies, as well as private industry, to prepare for and prevent new cases of WNV. Some things CDC is doing include: • Coordinating a nation-wide electronic database where states share information about WNV • Helping states develop and carry out improved mosquito prevention and control programs • Developing better, faster tests to detect and diagnose WNV • Creating new education tools and programs for the media, the public, and health professionals • Opening new testing laboratories for WNV • Working with partners on the development of vaccines What Else Should I Know? If you find a dead bird: Don't handle the body with your bare hands. Contact your local health department for instructions on reporting and disposing of the body. They may tell you to dispose fo the bird after they log your report. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 12 -
  13. 13. West Nile Virus --- Facts, Resources & Information Links to State and Local Government West Nile Virus Web Sites Click on a state to link directly to their West Nile virus Web page. See list below for additional city-level and main State Health Department Web sites. Maps and boundary data are copyrighted by FOTW Flags Of The World * • Expanded list of State and Local West Nile Virus Resources Maintained by the National Pesticide Information Center (NPIC) List of State and Local Health Department Web Sites, by State and City Health Department West Nile Virus Web Sites • Alabama • Alaska • Arizona • Arkansas • California o Los Angeles County Department of Health Services • Colorado • Connecticut o West Nile Fever Fact Sheet • Delaware • District of Columbia • Florida • Georgia o DeKalb County Board of Health DeKalb County Mosquitoes and West Nile Home Page • Hawaii • Idaho West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 13 -
  14. 14. West Nile Virus --- Facts, Resources & Information • Illinois • Indiana • Iowa • Kansas • Kentucky • Louisiana • Maine • Maryland • Massachusetts • Michigan • Minnesota • Mississippi • Missouri • Montana • Nebraska • Nevada • New Hampshire • New Jersey o New Jersey Department of Agriculture West Nile Virus Information o New Jersey West Nile Virus On-line Information Resources • New Mexico • New York o Monroe County Department of Health Monroe County West Nile Virus page o New York City Department of Health New York City Department of Health West Nile Virus Information o Westchester County Department of Health Westchester County West Nile Virus Watch • North Carolina • North Dakota • Ohio • Oklahoma • Oregon • Pennsylvania o Philadelphia Department of Public Health Philadelphia West Nile Virus Page • Rhode Island • South Carolina • South Dakota • Tennessee • Texas o Harris County Public Health Services • Utah • Vermont • Virginia • Washington • West Virginia • Wisconsin • Wyoming West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 14 -
  15. 15. West Nile Virus --- Facts, Resources & Information Add West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 15 -
  16. 16. West Nile Virus --- Facts, Resources & Information It's time to prepare for West Nile Virus. West Nile Virus is spread by mosquitoes. Infection with the virus can cause severe and sometimes fatal illness. There were over 4000 cases of West Nile disease in the US during 2002, including 284 deaths. It is likely that all mainland states in the United States will see West Nile virus activity in 2003. To help you prepare for mosquito season, read the truth about some common West Nile virus myths: Five Common Myths about West Nile Virus Myth #1: There's not much I can do about West Nile virus. Truth: There is a lot that you, personally, can do to reduce your chance of West Nile virus infection. West Nile Virus Guide • Reduce the number of mosquito bites you get. Make a habit of using insect repellent with DEET when outdoors. Spray repellent on exposed skin and clothing. Get the details about safe repellent use. • Prime mosquito-biting hours are usually dusk to dawn. Pay special attention to protection during these hours, or avoid being outdoors. • You can reduce the number of mosquitoes around your home. Mosquitoes breed in standing water, so check your yard once a week: get rid of containers that aren't being used, empty water from flower pots, change water in bird baths and maintain clean gutters. Avoid mosquito bites by applying insect repellent when spending time outdoors. Use repellent safely. Always read and follow product instructions. • Make sure window and door screens are in good condition. Have an older neighbor or family member? See if they need help installing or repairing screens. Myth #2: Kids are at the most danger of getting sick from West Nile virus. Truth: People over 50 are at the highest risk for developing severe West Nile disease. • Relatively few children have been reported with severe West Nile Virus disease. By contrast, most of the deaths due to WNV during 2002 were among people over 50 years old. Half of those deaths were among people over 77 years old. ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 16 -
  17. 17. West Nile Virus --- Facts, Resources & Information • It is always a good idea for children to avoid mosquito bites, but it's also important for adults - especially older adults - to take steps to avoid mosquito bites. Click here for suggestions on how to avoid mosquito bites. Myth #3: It's only people who are already in poor health who have to worry about West Nile virus. Truth: Healthy, active older adults who spend time working and exercising outdoors have been affected by severe West Nile virus infection. • Being over 50 is a risk factor for developing severe West Nile disease if infected with the virus. There is a risk of getting mosquito bites while leading an active life outdoors. This doesn't mean you have to stay inside - it does mean that it's important to use repellent when you go outside. Myth #4: Repellents containing DEET are not safe. Truth: Repellents containing DEET are very safe when used according to directions. • Because DEET is so widely used, a great deal of testing has been done. When manufacturers seek registration with the US Environmental Protection Agency (EPA) for products such as DEET, laboratory testing regarding both short- term and long-term health effects must be carried out. • There are products with different strengths (percentage of DEET) available. The longer the protection you need the higher percent of DEET needed. • Repellent with DEET can be used for both adults and children, according to directions • Click here for much more information on using repellents safely. Myth #5: As long as my area has a mosquito control program, I don't have to worry about using repellent. Truth: Mosquito control activities don't eliminate every mosquito, so personal protection is still important. • Public activities, such as using products to kill mosquito larvae and adult mosquitoes, are one part of control. Personal protection, such as using repellent, keeping window screens in good condition, and control of household breeding sites are other important steps. • Collaboration between the community, the family and the individual is needed to achieve the best prevention of West Nile virus infection. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 17 -
  18. 18. West Nile Virus --- Facts, Resources & Information West Nile Virus Transmission Cycle • Horses infected with West Nile Virus (WNV) are not contagious. • Horses can't spread it to other horses or people. • Mosquitoes that have fed on infected birds spread WNV. • A mosquito cannot bite an infected horse and spread the virus to another horse or person. • Horses are not known to spread West Nile Virus to people. Horses are considered to be "dead-end" hosts for WNV because it appears that they do not develop a sufficient viremia to transmit the virus from contact. Clinical signs are usually not apparent until 3-14 days post infection and viremia. Regardless, it is very important that veterinarians and other animal health workers take standard recommended precautions for all contagious equine viral encephalitic agents such as rabies and other viral encepaphalitis agents when dealing with horses suffering from undiagnosed neurological diseases. • Treatment consists of supportive measures, and there is no specific cure. • WNV is not analogous to Foot and Mouth Disease (FMD)) and Exotic Newcastle Disease (END). Both FMD and END are very contagious and spread with ease and rapidity. • There will be no quarantines nor regulatory movement restrictions placed on WNV positive horses. • Control of WNV in horses involves working with one's veterinary practitioner to establish both effective mosquito control and vaccination programs. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 18 -
  19. 19. West Nile Virus --- Facts, Resources & Information Add West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 19 -
  20. 20. West Nile Virus --- Facts, Resources & Information Fight The Bite! Avoid Mosquito Bites to Avoid Infection Fight The Bite! Avoid Mosquito Bites to Avoid Infection When dealing with West Nile virus, prevention is your best bet. Fighting mosquito bites reduces your risk of getting this disease, along with others that mosquitoes can carry. Take the commonsense steps below to reduce your risk: When dealing with West Nile virus, prevention is your best bet. Fighting mosquito bites reduces your risk of getting this disease, along with others that mosquitoes can carry. Take the commonsense steps below to reduce your risk: • avoid bites and illness;• avoid bites and illness; • clean out the mosquitoes from the places where you work and play;• clean out the mosquitoes from the places where you work and play; • help your community control the disease.• help your community control the disease. Something to remember: The chance that any one person is going to become ill from a single mosquito bite remains low. The risk of severe illness and death is highest for people over 50 years old, although people of all ages can become ill. Something to remember: The chance that any one person is going to become ill from a single mosquito bite remains low. The risk of severe illness and death is highest for people over 50 years old, although people of all ages can become ill. Avoid Mosquito Bites Use Insect Repellent on exposed skin when you go outdoors. Use an EPA-registered insect repellent such as those with DEET, picaridin or oil of lemon eucalyptus. Even a short time being outdoors can be long enough to get a mosquito bite. For details on when and how to apply repellent, see Insect Repellent Use and Safety in our Questions and Answers pages. See also Using Insect Repellent Safely from the EPA. Clothing Can Help Reduce Mosquito Bites When weather permits, wear long-sleeves, long pants and socks when outdoors. Mosquitoes may bite through thin clothing, so spraying clothes with repellent containing permethrin or another EPA-registered repellent will give extra protection. Don't apply repellents containing permethrin directly to skin. Do not spray repellent on the skin under your clothing.Get double protection: wear long sleeves during peak mosquito biting hours, and spray repellent directly onto your clothes. Be Aware of Peak Mosquito Hours The hours from dusk to dawn are peak biting times for many species of mosquitoes. Take extra care to use repellent and protective clothing during evening and early morning -- or consider avoiding outdoor activities during these times. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 20 -
  21. 21. West Nile Virus --- Facts, Resources & Information Mosquito-Proof Your Home Drain standing water from around your home Drain Standing Water Mosquitoes lay their eggs in standing water.Limit the number of places around your home for mosquitoes to breed by getting rid of items that hold water. Need examples? Learn more on the Prevention of West Nile Virus Question and Answer page. Install or Repair Screens Some mosquitoes like to come indoors. Keep them outside by having well-fitting screens on both windows and doors. Offer to help neighbors whose screens might be in bad shape. Help Your Community Report Dead Birds to Local Authorities Dead birds may be a sign that West Nile virus is circulating between birds and the mosquitoes in an area. Over 130 species of birds are known to have been infected with West Nile virus, though not all infected birds will die. It's important to remember that birds die from many other causes besides West Nile virus. By reporting dead birds to state and local health departments, you can play an important role in monitoring West Nile virus. State and local agencies have different policies for collecting and testing birds, so check the Links to State and Local Government Sites page to find information about reporting dead birds in your area. Click here for more info about reporting dead birds and dealing with bird carcasses. Mosquito Control Programs Check with local health authorities to see if there is an organized mosquito control program in your area. If no program exists, work with your local government officials to establish a program. The American Mosquito Control Association can provide advice, and their book Organization for Mosquito Control is a useful reference. The final report from the Mosquito Control Collaborative is also online. More questions about mosquito control? A source for information about pesticides West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 21 -
  22. 22. West Nile Virus --- Facts, Resources & Information and repellents is the National Pesticide Information Center, which also operates a toll-free information line: 1-800-858-7378 (check their Web site for hours). Clean Up Mosquito breeding sites can be anywhere. Neighborhood clean up days can be organized by civic or youth organizations to pick up containers from vacant lots and parks, and to encourage people to keep their yards free of standing water. Mosquitoes don't care about fences, so it's important to control breeding sites throughout the neighborhood. Find out more about local prevention efforts Find state and local West Nile virus information and contacts on the Links to State and Local Government Sites page. What You Need to Know about Mosquito Repellent Why You Should Use Mosquito Repellent Insect repellent helps reduce your exposure to mosquito bites that may carry West Nile virus or other diseases, and allows you to continue to play, work, and enjoy the outdoors with a lower risk of disease. When You Should Use Mosquito Repellent Use repellent when you go outdoors. You should use repellent even if you're only going outside for a few minutes-it only takes one bite to get West Nile virus. Many of the mosquitoes that carry the West Nile virus bite between dusk and dawn. If you're outside during these hours pay special attention to using repellent. Which Mosquito Repellents Work Best A wide variety of insect repellent products are available. CDC recommends the use of products containing active ingredients which have been registered with the U.S. Environmental Protection Agency (EPA) for use as repellents applied to skin and clothing. When EPA registers a repellent, they evaluate the product for efficacy and potential effects on human beings and the environment. EPA registration means that EPA does not expect a product, when used according to the instructions label, to cause unreasonable adverse effects to human health or the environment. Of the active ingredients registered with the EPA, two have demonstrated a higher degree of efficacy in the peer-reviewed, scientific literature.* Products containing West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 22 -
  23. 23. West Nile Virus --- Facts, Resources & Information these active ingredients typically provide longer-lasting protection than others: • DEET (N,N-diethyl-m-toluamide) • Picaridin (KBR 3023) Oil of lemon eucalyptus [p-menthane 3,8-diol (PMD)], a plant based repellent, is also registered with EPA. In two recent scientific publications, when oil of lemon eucalyptus was tested against mosquitoes found in the US it provided protection similar to repellents with low concentrations of DEET. These recommendations are for domestic use in the United States. See CDC Travelers’ Health website for specific recommendations concerning protection from insects when traveling outside the United States. In addition, certain products which contain permethrin are recommended for use on clothing, shoes, bed nets, and camping gear, and are registered with EPA for this use. Permethrin is highly effective as an insecticide and as a repellent. Permethrin- treated clothing repels and kills ticks, mosquitoes, and other arthropods and retains this effect after repeated laundering. The permethrin insecticide should be reapplied following the label instructions. Some commercial products are available pretreated with permethrin. Permethrin is not to be used directly on skin. How Often You Should Re-apply Repellents Follow the directions on the product you are using. Sweating or getting wet may mean that you need to re-apply more frequently. How the Percentage of Active Ingredient in a Product Relates to Protection Time In general, the more active ingredient (higher percentage) it has, the longer a repellent will protect you from mosquitoes. For example, DEET products are available in many formulations--something with 30% DEET will protect you longer than one with 5% DEET. You cannot directly compare the percentage of one active ingredient to another, however. Use your common sense. Re-apply repellent if you start to get bitten and follow the label instructions. As a “rule of thumb”: • For many hours outside (over 3-4 hours) and/or where biting is very intense—look for a repellent containing more than 20% DEET. Products with more than 50% DEET do not offer additional protection. • For shorter periods of time, repellents containing less than 20% DEET, the repellent currently available with 7% picaridin or one of the products containing oil of lemon eucalyptus may provide adequate protection. There are other products available, but they may not protect as long as those named here. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 23 -
  24. 24. West Nile Virus --- Facts, Resources & Information • Even if you’re going out for 10 minutes use a repellent —that’s long enough to get bitten! Hint: Applying permethrin to your clothing ahead of time will give you even greater protection. Remember—if you’re getting bitten, do something about it! Choose a repellent that you will use consistently. Also, choose a product that will provide sufficient protection for the amount of time that you will be spending outdoors. Product labels often indicate the length of time that you can expect protection from a product. If you are concerned about using insect repellent, consult your health care provider for advice. The National Pesticide Information Center (NPIC) can also provide information through a toll-free number, 1-800-858-7378 or http://npic.orst.edu. General Considerations for Using Repellents Safely • Always follow the instructions on the product label. • Apply repellents only to exposed skin and/or clothing (as directed on the product label.) Do not use repellents under clothing. • Never use repellents over cuts, wounds or irritated skin. • Do not apply to eyes or mouth, and apply sparingly around ears. When using sprays, do not spray directly on face—spray on hands first and then apply to face. • Do not allow children to handle the product. When using on children, apply to your own hands first and then put it on the child. You may not want to apply to children’s hands. • Use just enough repellent to cover exposed skin and/or clothing. Heavy application and saturation are generally unnecessary for effectiveness. If biting insects do not respond to a thin film of repellent, then apply a bit more. • After returning indoors, wash treated skin with soap and water or bathe. This is particularly important when repellents are used repeatedly in a day or on consecutive days. Also, wash treated clothing before wearing it again. (This precaution may vary with different repellents—check the product label.) • If you or your child get a rash or other bad reaction from an insect repellent, stop using the repellent, wash the repellent off with mild soap and water, and call a local poison control center for further guidance. If you go to a doctor because of the repellent, take the repellent with you to show the doctor. Note that the label for products containing oil of lemon eucalyptus specifies that they should not to be used on children under the age of three years. Other than those listed above, EPA does not recommend any additional precautions for using registered repellents on pregnant or lactating women, or on children. For additional information regarding the use of repellent on children, please see CDC’s Frequently Asked Questions about Repellent Use. DEET-based repellents applied according to label instructions may be used along with West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 24 -
  25. 25. West Nile Virus --- Facts, Resources & Information a separate sunscreen. No data are available at this time regarding the use of other active repellent ingredients in combination with a sunscreen. See http://www.epa.gov/pesticides/factsheets/insectrp.htm for additional information on using EPA-registered repellents. In addition to wearing repellent, you can protect yourself and your family by taking these precautions: • Wear clothing with long pants and long sleeves while outdoors. Apply permethrin or another EPA-registered repellent to clothing, as mosquitoes may bite through thin fabric. (Remember: don't use permethrin on skin.) • Use mosquito netting over infant carriers. • Reduce the number of mosquitoes in your area by getting rid of containers with standing water that provide breeding places for the mosquitoes. Updated Information regarding Insect Repellents Repellents are an important tool to assist people in protecting themselves from mosquito-borne diseases. A wide variety of insect repellent products are available. CDC recommends the use of products containing active ingredients which have been registered with the U.S. Environmental Protection Agency (EPA) for use as repellents applied to skin and clothing. EPA registration of repellent active ingredients indicates the materials have been reviewed and approved for efficacy and human safety when applied according to the instructions on the label. Of the active ingredients registered with the EPA, two have demonstrated a higher degree of efficacy in the peer-reviewed, scientific literature *. Products containing these active ingredients typically provide longer-lasting protection than others: • DEET (N,N-diethyl-m-toluamide) • Picaridin (KBR 3023) Oil of lemon eucalyptus [p-menthane 3,8-diol (PMD)], a plant based repellent, is also registered with EPA. In two recent scientific publications, when oil of lemon eucalyptus was tested against mosquitoes found in the US it provided protection similar to repellents with low concentrations of DEET. These recommendations are for domestic use in the United States. See CDC Travelers’ Health website for specific recommendations concerning protection from insects when traveling outside the United States. In addition, certain products which contain permethrin are recommended for use on clothing, shoes, bed nets, and camping gear, and are registered with EPA for this West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 25 -
  26. 26. West Nile Virus --- Facts, Resources & Information use. Permethrin is highly effective as an insecticide and as a repellent. Permethrin- treated clothing repels and kills ticks, mosquitoes, and other arthropods and retains this effect after repeated laundering. The permethrin insecticide should be reapplied following the label instructions. Some commercial products are available pretreated with permethrin. Length of protection from mosquito bites varies with the amount of active ingredient, ambient temperature, amount of physical activity/perspiration, any water exposure, abrasive removal, and other factors. For long duration protection use a long lasting (micro-encapsulated) formula and re-apply as necessary, according to label instructions. EPA recommends the following precautions when using insect repellents: • Apply repellents only to exposed skin and/or clothing (as directed on the product label.) Do not use repellents under clothing. • Never use repellents over cuts, wounds or irritated skin. • Do not apply to eyes or mouth, and apply sparingly around ears. When using sprays, do not spray directly on face—spray on hands first and then apply to face. • Do not allow children to handle the product. When using on children, apply to your own hands first and then put it on the child. You may not want to apply to children’s hands. • Use just enough repellent to cover exposed skin and/or clothing. Heavy application and saturation are generally unnecessary for effectiveness. If biting insects do not respond to a thin film of repellent, then apply a bit more. • After returning indoors, wash treated skin with soap and water or bathe. This is particularly important when repellents are used repeatedly in a day or on consecutive days. Also, wash treated clothing before wearing it again. (This precaution may vary with different repellents—check the product label.) • If you or your child get a rash or other bad reaction from an insect repellent, stop using the repellent, wash the repellent off with mild soap and water, and call a local poison control center for further guidance. If you go to a doctor because of the repellent, take the repellent with you to show the doctor. Note that the label for products containing oil of lemon eucalyptus specifies that they should not to be used on children under the age of three years. Other than those listed above, EPA does not recommend any additional precautions for using registered repellents on pregnant or lactating women, or on children. For additional information regarding the use of repellent on children, please see CDC’s Frequently Asked Questions about Repellent Use. [http://www.cdc.gov/ncidod/dvbid/westnile/qa/insect_repellent.htm] DEET-based repellents applied according to label instructions may be used along with a separate sunscreen. No data are available at this time regarding the use of other active repellent ingredients in combination with a sunscreen. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 26 -
  27. 27. West Nile Virus --- Facts, Resources & Information Vertebrate Ecology Transmission Cycle West Nile (WN) virus is amplified during periods of adult mosquito blood-feeding by continuous transmission between mosquito vectors and bird reservoir hosts. Infectious mosquitoes carry virus particles in their salivary glands and infect susceptible bird species during blood-meal feeding. Competent bird reservoirs will sustain an infectious viremia (virus circulating in the bloodstream) for 1 to 4 days after exposure, after which these hosts develop life-long immunity. A sufficient number of vectors must feed on an infectious host to ensure that some survive long enough to feed again on a susceptible reservoir host. View enlarged image. People, horses, and most other mammals are not known to develop infectious-level viremias very often, and thus are probably "dead-end" or incidental-hosts. Birds West Nile virus has been detected in dead birds of at least 138 species. Although birds, particularly crows and jays, infected with WN virus can die or become ill, most infected birds do survive. Click here for more information on species of dead birds in the U.S. in which West Nile virus has been detected. There is no evidence that a person can get WN virus from handling live or dead infected birds. Persons should avoid bare-handed contact when handling any dead animals, and use gloves or double plastic bags to place the bird carcass in a garbage bag or contact their local health department for guidance. Dogs and Cats West Nile virus does not appear to cause extensive illness in dogs or cats. There is a single published report of WN virus isolated from a dog in southern Africa (Botswana) in 1982. West Nile virus was isolated from a single dead cat in 1999. A serosurvey in New York City of dogs in the 1999 epidemic area indicated that dogs are frequently infected. Nonetheless, disease from WN virus infection in dogs has yet to be documented. There is no documented evidence of person-to-person or animal-to-person transmission of WN virus. Because WN virus is transmitted by infectious mosquitoes, dogs or cats could be exposed to the virus in the same way humans become infected. Veterinarians should take normal infection control precautions when caring for an animal suspected to have this or any viral infection. It is possible that dogs and cats could become infected by eating dead infected animals such as birds, but this is undocumented. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 27 -
  28. 28. West Nile Virus --- Facts, Resources & Information There is no reason to destroy an animal just because it has been infected with WN virus. Full recovery from the infection is likely. Treatment would be supportive and consistent with standard veterinary practices for animals infected with a viral agent. Horses Cases of WN virus disease in horses have been documented, either by virus isolation or by detection of WN virus-neutralizing antibodies in 1999, 2000, and 2001. Approximately 40% of equine WN virus cases results in the death of the horse. Horses most likely become infected with WN virus in the same way humans become infected, by the bite of infectious mosquitoes. In locations where WN virus is circulating, horses should be protected from mosquito bites as much as possible. Horses vaccinated against eastern equine encephalitis (EEE), western equine encephalitis (WEE), and Venezuelan equine encephalitis (VEE) are NOT protected against WN virus infection. A West Nile virus vaccine for horses was recently licensed, but its effectiveness is unknown. Horses infected by WN virus develop a brief low-level viremia that is rarely, if ever, infectious to mosquitoes. There is no reason to destroy a horse just because it has been infected with WN virus. Data suggest that most horses recover from the infection. Treatment would be supportive and consistent with standard veterinary practices for animals infected with a viral agent. Other Vertebrates Through December 2001, CDC has also received a small number of reports of WN virus infection in bats, a chipmunk, a skunk, a squirrel, and a domestic rabbit. Entomology Arthropod-borne viruses (termed "arboviruses") are viruses that are maintained in nature through biological transmission between susceptible vertebrate hosts by blood-feeding arthropods (mosquitoes, sand flies, ceratopogonids "no-see-ums", and ticks). Vertebrates can become infected when an infected arthropod bites them to take a blood meal. The term 'arbovirus' has no taxonomic significance. The arboviral encephalitides are zoonotic, being maintained in complex life cycles involving a nonhuman primary vertebrate host and a primary arthropod vector. These cycles usually remain undetected until humans encroach on a natural focus, or the virus escapes this focus via a secondary vector or vertebrate host as the result of some ecologic change. Humans and domestic animals can develop clinical illness but usually are incidental or "dead-end" hosts because they do not produce significant viremia (circulating virus), and thus do not contribute to the transmission cycle. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 28 -
  29. 29. West Nile Virus --- Facts, Resources & Information In the United States, West Nile virus is transmitted by infected mosquitoes, primarily members of the Culex species. Arboviral encephalitis can be prevented in two major ways: West Nile Virus Guide 1. Personal protective measures to reduce contact with mosquitoes and 2. Public health measures to reduce the population of infected mosquitoes in the environment. Personal protection measures include reducing time outdoors, particularly in early morning and evening hours, wearing long pants and long sleeved shirts, and applying mosquito repellent to exposed skin areas and clothing. Image: Culex mosquito laying eggs. (View enlarged image.) Public health measures include elimination of larval habitats or spraying of insecticides to kill juvenile (larvae) and adult mosquitoes. The combination of mosquito control methods selected for use in a control program depends on the time of year, the type of mosquitoes to be controlled, and the habitat structure. In emergency situations, wide area aerial spraying is used to quickly reduce the number of adult mosquitoes. In many states, aerial spraying may be available as a means to control nuisance mosquitoes. Such resources can be redirected to areas of virus activity when necessary. Financing of aerial spraying costs during disease outbreaks is often provided by state or local emergency funds. Federal funding of emergency spraying is rare and almost always is associated with a natural disaster such as flood or hurricane. Virology: Classification of West Nile Virus 1. Family: Flaviviridae 2. Genus: Flavivirus Japanese Encephalitis Antigenic Complex 3. Complex includes: Alfuy, Cacipacore, Japanese encephalitis, Koutango, Kunjin, Murray Valley encephalitis, St. Louis encephalitis, Rocio, Stratford, Usutu, West Nile, and Yaounde viruses. 4. Flaviviruses: share a common size (40-60nm), symmetry (enveloped, icosahedral nucleocapsid), nucleic acid (positive-sense, single stranded RNA approximately 10,000-11,000 bases), and appearance in the electron ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 29 -
  30. 30. West Nile Virus --- Facts, Resources & Information microscope. Therefore, images of West Nile virus are representative for this group of viruses. Public Health Confronts the Mosquito: Developing Sustainable State and Local Mosquito Control Programs Report by Association of State and Territorial Health Officials See "What You Can Do About Mosquito Control" Report Overview State and Local Mosquito Control Mosquito control is an important and basic public health function. The rapid spread of West Nile virus across the U.S. in the last five years demonstrates the continuing need for organized mosquito control activities. States and local communities are challenged to develop and maintain these essential vector control programs, especially in tight budgetary times and when emergency situations have quieted. The Association of State and Territorial Health Officials’ Mosquito Control Collaborative, a body comprised of state, local, and federal representatives from public health, environmental, and agricultural agencies, as well as other organizations closely involved with vector control and public health, has developed a report titled Public Health Confronts the Mosquito Control: Developing Sustainable State and Local Mosquito Control Programs. The report contains four sections discussing the major components of successful state and local mosquito control efforts: • Planning Ahead Understanding the structures and roles of the state, local and federal participants, defining workforce and training requirements, identifying legal authorities and funding alternatives, and developing strategies for evaluating programs are elements that should be included in any successful planning effort. States, localities, and the federal government all have active roles in mosquito control. The exact roles of each will differ among the individual states and localities. Whatever structure is chosen, it should be based on solid legal authority to act. The structure of the funding mechanism for mosquito control activities also impacts the ultimate sustainability of the program or activities. • Involving Others The foundation to any successful mosquito control action is involving key participants early in the process. Governments should develop a strategy for involving others, which includes identifying and engaging a wide variety of stakeholders. Governments West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 30 -
  31. 31. West Nile Virus --- Facts, Resources & Information should take care to identify the individuals, organizations, and agencies with a stake in mosquito control decisions. A variety of mechanisms should be used to target appropriate outreach to stakeholders. Special care should also be given to provide decision makers with solid information upon which to base policy. • Use the Best Science and Data It is critical that science drives the assessment of local and state needs, strategies selected, and design and monitoring of mosquito control programs. There are numerous proven methodologies and practices that guide the best mosquito control programs. All programs need to be based on an identified need that is matched with local and state resources and technically sound strategies. Access to epidemiologic capacity to conduct surveillance of mosquito-borne diseases in the human population, and monitor disease and the distribution of relevant animal and insect populations, is critical to begin any mosquito control activity. States and localities must also determine their mosquito control needs. A scientific response to combat nuisance mosquitoes may look very different from a program to combat mosquitoes carrying disease. • Informing the Public Mosquito control programs need the support of an informed public. Many of the successful strategies for control involve individuals, their families, and their neighborhoods. The public also has concerns about the problems related to mosquito populations and about insecticides and spraying. Development of a communications plan that includes public education about preventing the breeding of mosquitoes, personal protection guidance, and the activities and success of the agencies involved is critical to the success of the program. Conclusion Mosquito control is a multi-discipline effort that can and should involve many agencies and organizations at the local, state, and federal level. When programs are started for a specific disease threat, there is often a temptation to abandon control efforts once the threat has passed. As history demonstrates, the mighty mosquito always returns and frequently with a previously unknown and unpredictable disease threat. Public health has a responsibility and an opportunity to be part of a comprehensive and thoughtful approach to continued mosquito control through partnerships and teamwork at all levels of government. More information about state and local mosquito control programs and a copy of Public Health Confronts the Mosquito is available at www.astho.org/?template=mosquito_control.html. The report also contains Planning and Action checklists highlighting the major decision points and recommendations. Source: Public Health Confronts the Mosquito: Developing Sustainable State and Local Mosquito Control Programs. Association of State and Territorial Health Officials. (June 2005). Available at www.astho.org/?template=mosquito_control.html. What You Can Do About Mosquito Control • Find out about your local mosquito control program Contact them for information or questions about their mosquito control practices. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 31 -
  32. 32. West Nile Virus --- Facts, Resources & Information • Support mosquito control activities Report mosquito breeding sites untended pools, discarded tires, drainage ditches with standing water. • If your community doesn't have a mosquito control program Contact your local government officials (blue pages of the phone book) or health department. Information in the Public Health Confront the Mosquito (described above) provides guidance about starting a program. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 32 -
  33. 33. West Nile Virus --- Facts, Resources & Information Mosquitoes Each summer, hordes of these insects descend on backyards, parks and campgrounds. While most mosquitoes are merely nuisances, some can transmit serious diseases such as encephalitis and malaria in humans and heartworm disease in dogs. While the principles for west nile virus and mosquitoes are fairly common from state to state and generally worldwide, it would be impossible to discuss the specifics for all areas of the globe in a short volume such as this. So when possible I’ll relate to the west nile virus and mosquito control with regard to the state I live in, Illinois. Keep in mind this in no way denigrates the material in this book. All mosquitoes lay eggs in water, the virus is transferred via birds. Most specifics come from the Center for Disease Control and State Health Departments. What kinds of mosquitoes are common in Illinois? Two different kinds of mosquitoes plague Illinoisans. Floodwater (temporary pool) mosquitoes deposit their eggs singly in low-lying areas that will be flooded later. Under normal summer temperatures, large numbers of biting mosquitoes will emerge about two weeks after heavy rains and can be a major nuisance problem for several weeks. The most common of these in Illinois is the inland floodwater mosquito. A vicious biter, this mosquito will commonly fly 10 or more miles from where they hatch, particularly along prevailing winds. Floodwater mosquitoes have not been significant disease carriers in Illinois. Vector mosquitoes carry diseases and lay their eggs in stagnant ditches and sewage treatment ponds or water in treeholes, old tires, clogged gutters, old tin cans and anything else that will hold water. Eggs are laid on or just above the water surface, where they usually hatch within two to three days. Two of the more common vector mosquitoes in Illinois are the Culex, or house mosquito, and the tree-hole mosquito. Neither migrates long distances. Another disease-carrying mosquito is the Asian tiger mosquito, which arrived in the United States in 1985 in old tires. An aggressive day-biting mosquito, it breeds in large numbers in water-filled artificial containers. Do all mosquitoes carry disease? Floodwater mosquitoes are not major vectors of human disease in Illinois, but they do transmit heartworm disease in dogs, as do Culex mosquitoes. The worms live and reproduce in the heart and pulmonary vessels and can severely weaken or kill the dog. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 33 -
  34. 34. West Nile Virus --- Facts, Resources & Information Although difficult to treat, the disease is easily prevented by medication prescribed by a veterinarian. In Illinois, the most common human illness carried by mosquitoes is encephalitis. This inflammation of the brain is caused by viruses and the disease can range from mild to severe. Severe symptoms include rapid onset of severe headaches, high fever and mental disturbances, such as confusion, irritability, tremors, stupor and coma. Severe cases sometimes end in death or with survivors suffering permanent physical and mental disabilities. Mosquitoes do not carry all types of encephalitis virus, but they do carry at least three that can cause illness. The Culex mosquito, which bites from dusk to dawn, is a vector of St. Louis encephalitis and West Nile virus; it becomes infected by feeding on birds that carry these viruses. St. Louis encephalitis and West Nile virus affect mainly older adults. The tree-hole mosquito, which bites during the day, is the main vector of California (LaCrosse) encephalitis in Illinois. The virus infects chipmunks, squirrels and other small woodland animals; in humans, it affects mainly children. The Asian tiger mosquito transmits dengue fever in other parts of the world and could become involved in the California encephalitis cycle in Illinois. The last major nationwide epidemic of mosquito-borne encephalitis occurred in 1975. In Illinois, 578 cases of St. Louis encephalitis, which resulted in 47 deaths, and 23 cases of California encephalitis were identified during that year. When was West Nile virus found in Illinois? West Nile virus was first identified in September 2001 when laboratory tests confirmed its presence in two dead crows found in the Chicago area. The following year, the state's first human cases and deaths from West Nile disease were recorded and all but two of the state's 102 counties eventually reported a West Nile positive, human, bird, mosquito or horse. By the end of 2002, Illinois had counted more human cases (884) and deaths (66) than any other state in the nation. In 2003, the number of human cases fell to 54 and only one death, and West Nile activity was reported in 77 counties. What is the best way to reduce populations of mosquitoes? The first and best defense against these pests and the illnesses they may carry i to eliminate the places where they breed. Here are a few suggestions: s • Remove or empty water in old tires, tin cans, buckets, drums, bottles or other places where mosquitoes might breed. Be sure to check clogged gutters and flat roofs that may have poor drainage. Make sure cisterns, cesspools, septic tanks, fire barrels, rain barrels and trash containers are covered tightly with a lid or with 16-mesh screen. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 34 -
  35. 35. West Nile Virus --- Facts, Resources & Information • Empty plastic wading pools at least once a week and store indoors when not in use. Unused swimming pools should be covered or drained during the mosquito season. (Note: If you choose to drain your pool, be sure the hydrostatic relief valve is open in order to keep it from floating out of the ground if the water table rises.) • Change the water in bird baths and plant pots or drip trays at least once each week. • Store boats covered or upside down, or remove rainwater weekly. • Empty your pet's water bowl daily. • Level the ground around your home so water can run off and not collect in low spots. Fill in holes or depressions near your home that accumulate water. • Fill in tree rot holes and hollow stumps that hold water. • If you have an ornamental water garden, stock it with mosquito-eating fish (e.g., minnows, "mosquito fish," or goldfish). They eat mosquito larvae. • Keep weeds and tall grass cut short; adult mosquitoes look for these shady places to rest during the hot daylight hours. • Use a flyswatter or household spray to kill mosquitoes, flies or other insects that get into buildings. Spray shrubbery and high weeds to kill adult insects. (Check the insecticide label to make the sure the spray will not damage flowers or ornamental plants.) • Small impoundments of water can be treated for mosquito larvae with "Bti," a bacterial insecticide. Many hardware stores carry doughnut-shaped Bti briquets (Mosquito Dunks R) for this purpose. Be sure to follow the insecticide label directions exactly. • Some mosquito control methods are not very effective. Bug zappers are not effective in controlling biting mosquitoes. Various birds and bats will eat mosquitoes, but there is little scientific evidence that this reduces mosquitoes around homes. • Community-wide mosquito abatement efforts can be quite effective if they are conducted as part of an integrated pest management program. This includes monitoring and draining or treating areas where mosquitoes breed — such as street catch basins, occasionally flooded marshes, river backwater areas, swamps and other low-lying areas. How can people protect themselves from mosquito bites? • Avoid places and times when mosquitoes bite. Generally, the peak biting periods occur just before and after sunset and again just before dawn. Each species, however, has its own peak period of biting. Tree-hole and Asian tiger mosquitoes, for example, feed during daylight hours in or near shaded or wooded areas. • Be sure door and window screens are tight-fitting and in good repair. • Wear appropriate clothing. Long-sleeved tops and long pants made of tightly woven materials keep mosquitoes away from the skin. Be sure, too, that your clothing is light colored. Keep trouser legs tucked into boots or socks. • Use mosquito netting when sleeping outdoors or in an unscreened structure and to protect small babies any time. • When it is necessary to be outdoors, apply insect repellent as indicated on the repellent label. The more DEET a product contains, the longer the repellant can protect against mosquito bites. However, concentrations higher than 50 percent do not increase the length of protection. For most situations, 10 percent to 25 percent DEET is adequate. Apply repellents to clothes whenever possible; apply sparingly West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 35 -
  36. 36. West Nile Virus --- Facts, Resources & Information to exposed skin if label permits. Consult a physician before using repellents on young children. Mosquitoes and Encephalitis The Problem - Mosquito bites cause itching and irritation, and scratching may result in infected sores. Mosquitoes also transmit serious and sometimes fatal diseases to humans and their pets. Diseases - Encephalitis is an inflammation of the brain that can be caused by viruses. The symptoms of encephalitis can range from mild to severe. Severe symptoms include rapid onset of severe headaches, high fever, and mental disturbances such as confusion, irritability, tremors, stupor and coma. Severe cases sometimes end in death or with survivors suffering permanent loss of limb function, reduction of intelligence and/or emotional instability. Not all types of encephalitis viruses are carried by mosquitoes. However, mosquitoes carry at least two types of encephalitis viruses that cause human disease in Illinois. La Crosse (California) encephalitis is normally an infection of squirrels and chipmunks; in humans it affects mainly children. St. Louis encephalitis is an infection of wild birds; in humans it affects mainly older adults. Mosquitoes can also infect dogs with heartworm. The worms live in the heart and can severely weaken or kill the dog. Although difficult to treat, this disease is easily prevented by medication that can be prescribed by your veterinarian. Prevent Mosquitoes from Breeding Around the Home Mosquito larvae or "wrigglers" must live in still water for five or more days to complete their growth before changing into adult biting mosquitoes capable of transmitting disease. Often, the number of mosquitoes in an area can be reduced by removing sources of standing water. Hundreds of mosquitoes can come from a single discarded tire. • Get rid of old tires, tin cans, buckets, drums, bottles o any water-holding containers. r • Fill in or drain any low places (puddles, ruts, etc.) in the yard. • Keep drains, ditches, and culverts free of weeds and trash so water will drain properly. • Keep roof gutters free of leaves and other debris. • Cover trash containers to keep out rainwater. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 36 -
  37. 37. West Nile Virus --- Facts, Resources & Information • Repair leaky pipes and outside faucets. • Empty plastic wading pools at least once a week and store indoors when not in use. Unused swimming pools should be drained and kept dry during the mosquito season. • Fill in tree rot holes and hollow stumps that hold water. • Change the water in bird baths and plant pots or drip trays at least once each week. • Store boats covered or upside down, or remove rainwater weekly. • Keep grass cut short and shrubbery well trimmed around the house so adult mosquitoes will not hide there. Only a constant, complete program to control mosquitoes will reduce the numbers, the nuisance and the danger of disease. Protection from Mosquito Bites Although many kinds of mosquitoes bite at dusk or at night, some kinds will bite during the day. Almost all kinds will try to bite if you enter an area where they are resting, like high grass. • When possible, avoid places and times when mosquitoes bite. • Wear light-colored protective clothing: Tightly woven materials that cover arms and legs provide some protection from mosquito bites. Keep trouser legs tucked into boots or socks, and collars buttoned. • Have good screening: Make sure door and window screens fit tightly and all holes are repaired. • Use mosquito netting when sleeping outdoors or in an unscreened structure, and to protect small babies any time. • Small impoundments of water can be treated for mosquito larvae with "Bti," a bacterial insecticide. Many hardware stores carry doughnut-shaped Bti briquets (Mosquito Dunks R) for this purpose. Be sure to follow the insecticide label directions exactly. • When participating in outdoor activities where mosquitoes are biting, wear protective clothing (shoes, socks, shirt and long pants). For additional protection from mosquitoes, use an insect repellent. The more DEET a product contains, the longer the repellant can protect against mosquito bites. However, concentrations higher than 50 percent do not increase the length of protection. For most situations, 10 percent to 25 percent DEET is adequate. Apply repellents to clothes whenever possible; apply sparingly to exposed skin if label permits. Consult a physician before using repellents on young children. • Spraying your backyard with an insecticidal fog or mist is effective only for a short time. Mosquitoes will return when the effect of the spray has ended. • Insect light electrocutors ("bug zappers") or sound devices do little to reduce biting mosquitoes in an area. • Installing bird or bat houses to attract these insect-eating animals has been suggested as a method of mosquito control. However, there is little scientific evidence that this significantly reduces the mosquito population around homes. • Some communities conduct community-wide mosquito abatement programs. Whenever possible, the primary effort of such programs should be identification of mosquito-breeding sites, followed by removal or treatment of these sites with an insecticide used for control of mosquito larvae. West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 37 -
  38. 38. West Nile Virus --- Facts, Resources & Information Questions and Answers about Mosquito Prevention for People, Property and Pets What kinds of diseases can be carried by mosquitoes? Mosquito-borne disease is rare in Illinois. However, mosquitoes can carry at least three encephalitis viruses that cause human disease. La Crosse (California) encephalitis is normally an infection of squirrels and chipmunks; in humans it affects mainly children. St. Louis encephalitis is an infection of wild birds; in humans it affects mainly older adults. In 2001, West Nile virus (WNV) was detected for the first time in Illinois in birds, horses and mosquitoes. West Nile virus, like St. Louis encephalitis, causes encephalitis primarily in older adults. What is encephalitis? Encephalitis is an inflammation of the brain that can be caused by arboviruses (viruses carried by arthropods, such as mosquitoes and ticks) or by other types of viruses. In Illinois, arboviruses are primarily transmitted to humans by the bites of infected mosquitoes. Most individuals who are bitten by an infected mosquito will experience no symptoms of the disease or will have only very mild symptoms. Approximately 1 percent to 2 percent will develop recognizable symptoms. Some persons may have mild symptoms, such as a fever and headache. Severe infection may cause rapid onset of severe headache, high fever, muscle aches, stiffness in the back of the neck, problems with muscle coordination, disorientation, convulsions and coma. Symptoms usually occur five to 15 days after the bite of an infected mosquito. Not all viruses that cause encephalitis are carried by mosquitoes. How can I help protect my family and myself from mosquitoes and the diseases they may carry? During the summer, mosquitoes can develop in any standing water that lasts more than seven to 10 days. Consequently, you can begin protecting your family from mosquitoes by reducing the amount of standing water available for mosquito breeding around your home: • Dispose of discarded tires, cans, plastic containers, ceramic pots or other unused similar water-holding containers that have accumulated on your property. Do not West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 38 -
  39. 39. West Nile Virus --- Facts, Resources & Information overlook containers that have become overgrown by vegetation. • At least once per week, empty standing water from containers on your property, such as tire swings, or bird baths. • Fill in tree rot holes and hollow stumps that hold water. • Drill holes in the bottom of recycling containers that are left outdoors. Drainage holes drilled in the sides of containers allow sufficient water to collect in which mosquitoes may breed. • Clean clogged roof gutters, particularly if the leaves from surrounding trees have a tendency to plug up the drains. Flooded roof gutters are easily overlooked but can produce hundreds of mosquitoes each season. • Turn over plastic wading pools when not in use. A wading pool becomes a mosquito producer if it is not used on a regular basis. • Turn over wheelbarrows and do not allow water to stagnate in bird baths. Change water in bird baths and wading pools on a weekly basis. • Store boats covered or upside down, or remove rainwater weekly. • Aerate ornamental pools or stock them with fish. Water gardens are fashionable but become major mosquito producers if they are allowed to stagnate. • Clean and chlorinate swimming pools that are not being used. A swimming pool that is left untended by a family that goes on vacation for a month can produce enough mosquitoes to result in neighborhood-wide complaints. Be aware that mosquitoes may breed in the water that collects on swimming pool covers. • Keep drains, ditches and culverts free of grass clippings, weeds and trash so water will drain properly. • Fill in low areas on your property to eliminate standing water. Ponds or streams where fish are present or the water is disturbed by current or wave action do not produce many mosquitoes. • Report possible mosquito breeding sites to your local mosquito control agency if one exists in your community. Should we stay indoors? It is not necessary to limit outdoor activities unless there is evidence of mosquito-borne disease in your area. However, you can and should try to reduce the risk of being bitten by mosquitoes. • Minimize time spent outdoors between dusk and dawn when mosquitoes are most active. Northern house mosquito (Culex pipiens) 1 West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 39 -
  40. 40. West Nile Virus --- Facts, Resources & Information • Be sure door and window screens are tight-fitting and in good repair. • Wear shoes, socks, long pants and a long-sleeved shirt when outdoors for long periods of time, or when mosquitoes are most active. Clothing should be light colored and made of tightly woven materials to keep mosquitoes away from the skin. • Use mosquito netting when sleeping outdoors or in an unscreened structure and to protect small babies when outdoors. • When it is necessary to be outdoors, apply insect repellent as indicated on the repellent label. The more DEET a product contains, the longer the repellant can protect against mosquito bites. However, concentrations higher than 50 percent do not increase the length of protection. For most situations, 10 percent to 25 percent DEET is adequate. Apply repellents to clothes whenever possible; apply sparingly to exposed skin if label permits. Consult a physician before using repellents on young children. • Insect light electrocutors ("bug zappers") or sound devices do little to reduce biting mosquitoes in an area. • Spraying your backyard with an insecticidal fog or mist is effective only for a short time. Mosquitoes will return when the effect of the spray has ended. • Installing bird or bat houses to attract these insect-eating animals has been suggested as a method of mosquito control. However, there is little scientific evidence that this significantly reduces the mosquito population around homes. Can pets and livestock get WNV infection? Horses can become infected with WNV if bitten by mosquitoes that carry the virus. There is a published report of West Nile virus isolated from a dog in southern Africa (Botswana) in 1982. West Nile virus has been isolated from several dead cats in 1999 and 2000. A blood of dogs and cats in the epidemic area showed a low infection rate. What signs of infection should I look for in domestic animals? West Nile virus and other mosquito-borne viruses can cause encephalitis in domestic animals. Sick animals may have a fever, weakness, poor muscle coordination, muscle spasms and signs of a neurological disease, such as change in temperament or seizures. What should I do if I suspect my pet has WNV? If your animal is sick, contact your veterinarian. The veterinarian will evaluate your animal, provide treatment and forward samples for laboratory testing to rule out other possible diseases. The Illinois Department of Agriculture can help veterinarians determine if WNV is the cause once the illness is reported. Can you get WNV directly from birds, game or domestic animals? The risk to humans and domestic animals is from the bite of WNV-infected mosquitoes. Although there is no evidence of human infection from handling infected live or dead animals, the U.S. Centers for Disease Control and Prevention recommends that anyone handling sick or dead animals avoid bare-handed contact. Hunters should use gloves when cleaning game animals and persons disposing of dead birds should use a shovel, gloves or West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 40 -
  41. 41. West Nile Virus --- Facts, Resources & Information double plastic bags to place carcasses in a garbage can. After disposing of the carcass, thoroughly wash your hands with soap and warm water. Veterinarians should use normal veterinary infection control precautions when caring for a horse suspected to have this or any other infection. Is there a vaccine for pets and livestock for WNV? A vaccine is available to protect horses from WNV infection; vaccines for other domestic animals are not available currently. How is WNV infection in domestic animals treated? As in people, there are no specific treatments for WNV infection in domestic animals. Treatment is primarily supportive to lessen the severity of the symptoms. How can I protect pets and livestock from WNV infection? You can reduce the risk of WNV infection in animals by minimizing their exposure to infected mosquitoes. Questions and Answers about Spraying for Adult Mosquitoes How are adult mosquitoes controlled? Mosquito control agencies use truck-mounted fogging units to apply insecticides as an ultra-low-volume (ULV) spray. ULV spray units dispense very fine aerosol droplets (fog) that stay aloft and kill mosquitoes on contact. The amount of insecticide sprayed by ULV units is small compared to the area treated, usually about 3 to 5 ounces per acre, which minimizes exposure and risks to people and the environment. Some communities have thermal foggers that use an oil carrier that is heated to disperse the pesticide in a dense smoke-like fog. What agency conducts mosquito control in my town? With a few exceptions, where mosquito control is conducted, it is locally funded and carried out by village or city governments. Some communities are part of a local government agency called a mosquito abatement district that receives local property taxes to conduct mosquito contr operations. ol Why is the local government fogging for mosquitoes in my community? West Nile Virus Guide ------------------------------------------------------------------------------------------------------------ ©All Rights Reserved www.WestNileVirusGuide.con Page - 41 -

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