Zika virus is primarily spread by mosquitoes and can cause serious birth defects. Learn about areas at risk, the illness it causes, and ways to prevent it.

1. ZIKA VIRUS
Prepared By
Mrs. Krupa Mathew.M,
Associate Professor

2. ZIKA
 Zika virus infection is a mild febrile viral illness transmitted by
mosquitoes. The Zika virus is a member of the Flavivirus genus in
the family Flaviviridae.
 It is related to dengue, yellow fever, West Nile and Japanese
encephalitis, viruses that are also members of the virus family
Flaviviridae..
 It was discovered in the Zika forest in Uganda in 1947.
 The Zika virus' incubation period is about 3 to 12 days after the bite
of an infected
mosquito.
 The vast majority of infections are not contagious from person to
person.

3. Zika virus Epidemiology
 The very first known case of Zika fever was in a rhesus monkey in the Zika
Forest in Uganda in 1947.
 The first human cases were reported in Nigeria in 1954. A few outbreaks have
been reported in tropical Africa and in some areas in Southeast Asia.
 The first major outbreak, with 185 confirmed cases, was reported in 2007 in the
Yap Islands of the Federated States of Micronesia.
 In 2013 another large outbreak was reported in French Polynesia that was thought
to be from an independent introduction of the virus from Asia than the Yap Island
outbreak.
 In May 2015, the Pan American Health Organization (PAHO) issued an alert
regarding the first confirmed Zika virus infections in Brazil. Mosquito-borne Zika
virus is suspected to be the cause of 2,400 cases of microcephaly and 29 infant
deaths in Brazil in 2015.

4.  The emergence of Zika virus in South America led to a rapid spread
throughout South and Central America, reaching Mexico in November
2015.
 It has appeared sporadically in travellers to the United States and Europe.
 Because of the "growing evidence of a link between Zika and microcephaly"
the CDC issued a travel alert on January 15, 2016 advising pregnant
women to consider postponing travel to the following countries and
territories: Brazil, Colombia, El Salvador, French Guiana, Guatemala,
Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Suriname,
Venezuela, and the Commonwealth of Puerto Rico.
 The agency also suggested that women thinking about becoming pregnant
should consult with their physicians before traveling.

5. Transmission of zika virus
 Through mosquito bites:
 Zika virus is transmitted to people primarily through the bite of an
infected Aedes species
mosquito (A. aegypti and A. albopictus).
 These mosquitoes typically lay eggs in and near standing water in
things like buckets, bowls, animal dishes, flower pots and vases.
They prefer to bite people, and live indoors and outdoors near
people.
 Mosquitoes that spread chikungunya, dengue, and Zika are
aggressive daytime biters. They can
also bite at night.
 Mosquitoes become infected when they feed on a person already
infected with the virus. Infected mosquitoes can then spread the
virus to other people through bites.

6.  From mother to child:
 A mother already infected with Zika virus near the time of delivery
can pass on the virus to her newborn around the time of birth.
 It is possible that Zika virus could be passed from a mother to her
baby during pregnancy.
 To date, there are no reports of infants getting Zika virus
through breastfeeding. Because of the benefits of breastfeeding,
mothers are encouraged to breastfeed even in areas where Zika
virus is found.

7.  Through sexual contact:
 Zika virus is transmitted to the people through sexual activity.
 Dallas County Health and Human Services (DCHHS) has received
confirmation from the Centers for Disease Control and Prevention
(CDC) of the first Zika virus case acquired through sexual
transmission in Dallas County in 2016.
 The patient was infected with the virus after having sexual contact
with an ill individual who returned from Venezuela,a country
where Zika virus is present.

8. Symptoms of Zika virus
 Low-grade fever (between 37.8°C and 38.5°C)
 Arthralgia, notably of small joints of hands and feet, with possible
swollen joints
 Myalgia
 Headache, retro-ocular headaches
 Conjunctivitis
 Cutaneous maculopapular rash
 Post-infection asthenia which seems to be frequent.
 More rarely observed symptoms include
 Digestive problems
 Abdominal pain
 Diarrhea
 Constipation mucous membrane
 Ulcerations
 Pruritus

9. Risk of Zika during pregnancy
 According to pediatric neurologists in Brazil that some pregnant women infected by zika
virus have given birth to the babies with a birth defect called microcephaly.
 Microcephaly, which comes from the Greek words for small head is a broad term used to
describe a smaller-than-average head circumference in babies (at least two standard
deviations below the mean for his or her sex and age). It can be caused by a wide range of
things, from diseases to malnutrition.
 Because of the potential for birth defects, the CDC(Centers for Disease Control and
Prevention) issued travel guidance for pregnant American women and women of
childbearing age who may become pregnant, warning them to avoid visiting places where
the virus is currently circulating.

10. Diagnosis
 IgM, IgG and PCR for Zika virus.
 Acute serum (taken within 5 days of symptom onset) and
convalescent serum (2–3 weeks later) should be taken. The two
samples are important to rule out false positive tests due to cross
reactivity with similar viruses such as Dengue.
 Provide overseas travel details and clinical history including the
onset day and patient’s DHB. Onset date is extremely important
to ensure that the most appropriate test is performed.
 The local laboratory will forward samples to ESR who will arrange
testing at an Australian Arbovirus Reference Laboratory (no labs in
NZ currently test for Zika virus).

11. Precaution & prevention
 Prevention involves reducing mosquito populations and avoiding bites,
which occur mainly during the day. Eliminating and controlling Aedes
aegypti mosquito breeding sites reduces the chances that Zika will be
transmitted. An integrated response is required, involving action in
several areas, including health, education, and the environment.
 To eliminate and control the mosquito, it is recommended to:
 Avoid allowing standing water in outdoor containers (flower pots, bottles,
and containers that collect water) so that they do not become mosquito
breeding sites.
 Cover domestic water tanks so that mosquitoes cannot get in.
 Avoid accumulating garbage: Put it in closed plastic bags and keep it in
closed
containers.
 Unblock drains that could accumulate standing water.

12.  Use screens and mosquito nets in windows and doors to
reduce contact between mosquitoes and people
 To prevent mosquito bites, it is recommended that people who live
in areas where there are cases of the disease, as well as travelers
and, especially, pregnant women should:
 Cover exposed skin with long-sleeved shirts, trousers, and hats
 Use repellents recommended by the health authorities (and apply
them as indicated on the
label)
 Sleep under mosquito nets.
 People with symptoms of Zika, dengue, or chikungunya should visit
a health center.

13. Treatment
 There is no commercial vaccine or specific antiviral drug
treatment for Zika virus infection.
 Treatment is directed primarily at relieving symptoms using
anti-pyretics and analgesics.