Zika virus, a member of flaviviridae, was first identified in 1947
in Uganda in rhesus monkeys and subsequently in humans in 1952. It is an
emerging mosquito-borne virus and its outbreaks have been reported in Africa,
the Americas, Asia and the Pacific.
Signs and Symptoms
Following an incubation period
that is likely to be a few days, the symptoms include fever, skin rashes,
conjunctivitis, muscle and joint pain, malaise, and headache. These symptoms
are usually mild and last for 2-7 days. During large outbreaks in French
Polynesia and Brazil in 2013 and 2015 respectively, potential neurological and
auto-immune complications of Zika virus disease were reported. Recently in
Brazil, an increase in Zika virus infections in the general public as well as
an increase in babies born with microcephaly in northeast Brazil were observed.
There have been increasing body of evidence about the link between Zika virus
Zika virus is transmitted to
people through the bite of an infected mosquito from theAedes genus,
mainly Aedes aegypti in tropical regions. This is the same
mosquito that transmits dengue, chikungunya and yellow fever.
Zika virus disease outbreaks
were reported for the first time from the Pacific in 2007 and 2013 (Yap and
French Polynesia, respectively), and in 2015 from the Americas (Brazil and
Colombia) and Africa (Cape Verde). In addition, more than 13 countries in the
Americas have reported sporadic Zika virus infections indicating rapid
geographic expansion of Zika virus. A case of sexual transmission of Zika virus
is reported recently from Texas, US.
Zika virus is diagnosed through
PCR (polymerase chain reaction) and virus isolation from blood samples.
Diagnosis by serology can be difficult as the virus can cross-react with other
flaviviruses such as dengue, West Nile and yellow fever.
Mosquitoes and their breeding
sites pose a significant risk factor for Zika virus infection. Prevention and
control relies on reducing mosquitoes through source reduction (removal and
modification of breeding sites) and reducing contact between mosquitoes and
Zika virus disease is usually
relatively mild and requires no specific treatment. People sick with Zika virus
should get plenty of rest, drink enough fluids, and treat pain and fever with
common medicines. If symptoms worsen, they should seek medical care and advice.
Currently, there is no vaccine available.