West Nile virus is spread through mosquito bites and can cause mild to severe illness. Most people infected have no symptoms, but some experience fever, headache, body aches, and swollen lymph nodes. In rare cases it can cause encephalitis or meningitis. There is no treatment other than supportive care. Risk factors include age over 50, time spent outdoors, and blood transfusions. Prevention involves mosquito control and personal protection measures like repellent and protective clothing.

1. Fitango Education
Health Topics
West Nile Virus
http://www.fitango.com/categories.php?id=212

2. Overview
West Nile virus (WNV) is an infectious disease that
first appeared in the United States in 1999. WNV is
spread when mosquitos infected with the disease
bite humans or animals. People who contract WNV
usually have no symptoms or mild symptoms.
Those with symptoms may have a fever, headache,
body aches, skin rash or swollen lymph glands.
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3. Overview
If West Nile virus enters the brain, it can be deadly.
It may cause inflammation of the brain, called
encephalitis, or inflammation of the tissue that
surrounds the brain and spinal cord, called
meningitis.
http://www.nlm.nih.gov/medlineplus/westnileviru
s.html
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4. Symptoms
Some people infected with WNV will develop
severe illness. The severe symptoms can include
high fever, headache, neck
stiffness, stupor, disorientation, coma, tremors, co
nvulsions, muscle weakness, vision loss, numbness
and paralysis. These symptoms may last several
weeks, and neurological effects may be
permanent.
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5. Symptoms
Up to 20 percent of the people who become
infected have milder symptoms such as fever,
headache, 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.
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6. Symptoms
Approximately 80 percent of people (about 4 out
of 5) who are infected with WNV will not show any
symptoms at all.
http://www.cdc.gov/ncidod/dvbid/westnile/wnv_f
actsheet.htm
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7. Diagnosis
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.
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8. Diagnosis
People typically develop symptoms between 3 and
14 days after
they are bitten by the infected
mosquito.
http://www.cdc.gov/ncidod/dvbid/westnile/wnv_f
actsheet.htm
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9. Treatment
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.
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10. Causes
West Nile Virus is caused by the following:
-- 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.
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11. Causes
-- 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.
http://www.cdc.gov/ncidod/dvbid/westnile/wnv_f
actsheet.htm
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12. Risks
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.
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13. Risks
Being outside means also you're at risk. The more
time you are outdoors, the more time likely you
are to be bitten by an infected mosquito. Pay
attention to avoiding mosquito bites if you spend a
lot of time outside.
**Other possible risks include**
:
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14. Risks
-- Donated Blood. All donated blood is checked for
WNV before being used. The risk of getting WNV
through blood transfusions and organ transplants
is very small, but if you have concerns, talk to your
doctor about the risks.
-- Pregnancy and Nursing. The risk that WNV may
be passed down to a fetus or infant through
breastmilk is still being evaluated. Talk to your
health care provider if you have questions.
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15. Risks
http://www.cdc.gov/ncidod/dvbid/westnile/wnv_f
actsheet.htm
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16. Prevention
Prevention measures consist of community-based
mosquito control programs that are able to reduce
vector populations, personal protection measures
to reduce the likelihood of being bitten by infected
mosquitoes, and the underlying surveillance
programs that characterize spatial/temporal
patterns in risk that allow health and vector
control agencies to target their interventions and
resources.
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17. Prevention
****
**The easiest way to avoid WNV is to prevent
mosquito bites**
:
-- When outdoors, use insect repellent with an
EPA-registered active ingredient
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18. Prevention
****
-- Get rid of mosquito breeding sites by emptying
standing water from flower pots, buckets or
barrels. Change water in bird baths and pet dishes
weekly. -Keep children's wading pools empty when
they aren't being used
-- Wear long sleeves and pants, if possible
-- Stay indoors between dusk and dawn, when
mosquitoes are most active
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19. Prevention
****
-- Use screens on windows to keep mosquitoes out
*Older people are more at risk for West Nile
Virus, so they should be especially careful.
http://www.cdc.gov/ncidod/dvbid/westnile/wnv_f
actsheet.htm
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