Zika virus was first isolated in 1947 in Uganda. It spread from Africa to Asia between 1951-1981 and caused its first outbreak outside of Africa and Asia on Yap Island in 2007. In 2015, Zika virus emerged in Brazil and has since spread across South and Central America. The main reasons for the outbreak in the Americas include lack of prior exposure or immunity, presence of the Aedes mosquito vector, and living conditions conducive to mosquito breeding. Zika virus is alarming due to its association with microcephaly in babies born to infected mothers and the lack of vaccines or treatments.

1. Prepared by
Basem Hamed

2. History of zika
1947- First evidence of zika virus
 April 1947 - The virus was first isolated from a rhesus monkey placed in a
cage in the Zika Forest of Uganda, near Lake Victoria
 Jan 1948 - Second isolation from the mosquito A. africanus at the same site
 1952 - Virus isolated from the serum of the monkey with fever and it was first
described as ZIKA VIRUS

3. 1952- First evidence of human infection
 Serosurvey carried out in 84 people of all ages showed antibodies, all above 40
years of age were immune
 Following an outbreak investigation of jaundice suspected to be yellow fever in the
blood of a 10 year old Nigerian female, Zika virus was successfully isolated using
laboratory mice.
 Infection was proven by a rise in Zika virus specific serum antibodies

4. 1951-1981 - Spread from equatorial Africa to Asia
 Evidence of human infection with Zika virus was reported from other African
countries
* Central African Republic *Egypt
*Gabon *Sierra Leone
*Tanzania, and Uganda.
 Also reported in parts of Asia including India, Indonesia, Malaysia, the Philippines,
Thailand, and Vietnam

5. April 2007- First outbreak outside of Africa and Asia
 Occurred on the island of Yap in the Federated States of Micronesia
 characterized by rash, conjunctivitis, and arthralgia, which was initially thought to be
dengue or Ross River disease
 Serum samples from patients in the acute phase of illness contained RNA of Zika
virus
 There were 49 confirmed cases, 59 unconfirmed cases, no hospitalizations, and no
deaths.
 More recently, epidemics have occurred in Polynesia, Easter Island, the Cook Islands
and New Caledonia

6. May 2015- Present - Outbreak in the Americas
 Began in May 2015 in Brazil. In May 2015, Zika virus was first confirmed as the
cause of an outbreak of a dengue-like disease in northern and eastern Brazil, reported
by Pan American Health Organization (PAHO).
 Brazilian researchers have suggested that the Zika virus arrived in the country from
French Polynesia during the 2014 FIFA World Cup tournament
 Subsequently spread to other countries in South America, Central America, Mexico
and the Caribbean.
 Cases have also been reported that were imported from South America into Europe
and the United States.

8.  January 2016, the U.S. CDC issued a travel alert for people traveling to regions and
certain countries where Zika virus transmission is ongoing.
 No locally transmitted Zika cases have been reported in the continental United States,
but cases have been reported in returning travelers.
 February 2016- WHO declared that microcephaly and Guillain-Barré syndrome, believed to be
associated with the virus outbreak.
 Between October 2015 and January 2016 – 3500 microcephaly cases (Brazilian
health authority)
 In the worst affected region of Brazil, approximately 1 percent of newborns are
suspected of being microcephalic.

12. Reasons for outbreak
• First - Zika didn't seem to pose much risk to humans, this virus wasn't exactly on the
world's watch list. It wasn't even a reportable disease in the US
• Second - Zika had never been recorded in the Western Hemisphere until it hit Easter
Island off Chile in 2014. That means people living in the Americas are susceptible to
the virus, since nobody has built up the antibodies from previous infections to fight it
off.
• Third - Aedes mosquitoes live all over Latin America. Couple that with the fact
that many people live in communities that are perfectly hospitable to these insects:
There's little air conditioning and window screens (to keep mosquitoes out) as well as
poor sanitation and a lack of access to clean water (so people store water around their
homes)
Source: http://www.vox.com/2016/2/2/10893526/zika-virus-disease-spread-history-cases

14. Why is this Outbreak Alarming?
 Zika virus is catching global attention due to its alarming connection with
microcephaly, a neurological disorder in babies being born with abnormally small
heads.
 In 2015, there were 3500 cases of microcephaly compared with 147 in 2014 and 167
in 2013.
 In January 2016, a baby in Hawaii, the first case with microcephaly in the United
States linked to the virus.

16. What is zika virus?
• Zika virus is a mosquito-borne virus
• Member of the virus family Flaviviridae and the genus Flavivirus
• Vector: Aedes mosquitoes (which usually bite during the morning and late
afternoon/evening hours). This is the same mosquito that transmits dengue and
yellow fever.
• Incubation period – 3-7 days

17. Structure
• Group IV: (+) sense single-stranded RNA virus

18. How is it transmitted?
• Through bite of an infected mosquito from the Aedes genus
• Mother to fetus during pregnancy
• Through blood transfusion
• sexual contact

19. Vectors
• A. aegypti,
• A. africanus
• A. apicoargenteus
• A. furcifer
• A. hensilli
• A. luteocephalus and A. vitattus

20. ZIKA VIRUS CROSS PLACENTA
• Maternal-fetal transmission of Zika virus has been documented throughout
pregnancy.
• No evidence exists to suggest that pregnant women are more susceptible to Zika
virus infection or experience more severe disease during pregnancy.
• Although Zika virus RNA has been detected in the pathologic specimens of fetal
losses, it is not known if Zika virus caused the fetal losses.

21. Sexual transmission of zika virus
 There have been three cases in the medical literature that suggest Zika can be
sexually transmitted.
 In one case, a man who traveled to Senegal in 2008 and contracted Zika transmitted
to his wife through intercourse after he returned home to Colorado.
 In another, Zika was isolated from semen.
 The third case of sexual transmission during the current outbreak was documented in
Dallas in February: A traveler returned from Venezuela, where the virus was
circulating, and infected his or her partner. (unpublished data, 2016, Dallas County
Health and Human Services).
 In all three cases, the men developed symptomatic illness.
 Sexual transmission of Zika virus from infected women to their sex partners has not
been reported.

22. Breastfeeding?
• There is no evidence that zika virus sheds in breastmilk.
• Mothers are encouraged to breastfeed infants even in areas where Zika
virus is found, as available evidence indicates the benefits of
breastfeeding outweigh any theoretical risks associated with Zika virus
infection transmission through breast milk

24. Symptoms
• About 1 in 5 people infected with Zika virus become ill.
• The most common symptoms of Zika are
 fever
 rash
 joint pain
 conjunctivitis
 muscle pain
 headache.

26. Testing for zika
• There are no commercially available diagnostic tests for Zika virus disease.
• Zika virus testing is performed at the CDC Arbovirus Diagnostic Laboratory and a
few state or local health departments.
• Test results are normally available 4 to 14 days after specimen receipt.
• Methods:-
1. Reverse transcriptase-polymerase chain reaction (RT-PCR) on serum.
2. Immunoglobulin IgM ELISA
3. ( Plaque-reduction neutralization testing )can be performed to discriminate between
cross-reacting antibodies in primary flavivirus infections.

27. Prevention
• Prevention and control relies on reducing mosquitoes through source reduction
(removal and modification of breeding sites) - empty, clean or cover containers that
can hold water such as buckets, flower pots or tyres
• Reducing contact between mosquitoes and people by using insect repellent;
wearing clothes that cover as much of the body as possible; using physical barriers
such as screens, closed doors and windows; and sleeping under mosquito nets.

29. Treatment
 No specific antiviral treatment is available for Zika virus disease.
 Treatment is generally supportive and can include rest, fluids, and use of analgesics
and antipyretics.
 In a pregnant woman with laboratory evidence of Zika virus in serum or amniotic
fluid, serial ultrasounds should be considered to monitor fetal anatomy and growth
every 3–4 weeks.
 Referral to a maternal-fetal medicine or infectious disease specialist with expertise in
pregnancy management is recommended.

32. CDC Recommendations to pregnant women
 Recommendations for Pregnant Women (Considering Travel) to an
Area of Zika Virus Transmission.
 CDC recommends postponing travel to areas where Zika virus transmission is
ongoing If travel required, strictly follow steps to avoid mosquito bites
throughout the entire day (Follow prevention strategies - wearing long-sleeved shirts
and long pants, insect repellents, using permethrin-treated clothing and sleeping in
screened-in or air-conditioned rooms) .

33. Women who traveled to an area
with ongoing Zika virus
transmission during pregnancy
should be evaluated for Zika
virus infection and tested in
accordance with CDC
Guidance.
Recommendations for Pregnant Women with (History of Travel) to an Area of Zika
Virus Transmission

34. CDC Guidelines for Prevention of Sexual Transmission of
Zika Virus
Recommendations for men and their partners
 After infection, Zika virus might persist in semen when it is no longer detectable in
blood.
 Avoid sexual activity
 Use condoms during sex, for the duration of the pregnancy

35. Question &
Answers

36. Should pregnant women travel to places
with Zika outbreaks?
• Pregnant women in any trimester should consider
postponing travel to any area where Zika virus is
spreading. If you must travel to one of these areas, talk to
your healthcare provider first and strictly follow steps to
prevent mosquito bites during your trip.

37. Should women trying to get pregnant
travel to places with Zika outbreaks?
• CDC recommends that women trying to get pregnant and
their male partners talk to their healthcare provider before
traveling to areas with Zika because sexual transmission
is possible.
• Both men and women should strictly follow steps
to prevent mosquito bites during the trip.

38. Can mothers pass Zika to their fetuses
during pregnancy?
• YES, Zika virus can be passed from a mother to her fetus
during pregnancy.

39. Can a pt e previous Zika infection in
who later gets pregnant to have a baby
with microcephaly?
• no evidence as Zika virus usually remains in the blood of
an infected person for about a week.

40. Is there a vaccine or medicine for Zika?
• NO

41. Can pregnant and breastfeeding women
use insect repellent?
• Yes. Use EPA-registered insect repellents. When used as
directed, these insect repellents are proven safe and
effective even for pregnant and breastfeeding women

42. Should a pregnant woman who has
traveled to a place with a Zika outbreak
be tested for the virus?
• CDC recommends that all pregnant women who have
traveled to a place with a Zika outbreak get tested
especially those developing symptoms during their trip or
within 2 weeks after traveling to an area with Zika

44. Key facts