Zika is an emerging arbovirus that is spread directly from mosquitoes to humans and vice versa, unlike other arboviruses that are permanently established and spread through bridge vectors, such as birds. The possible vector of Zika in this area is Aedes albopictus, the Asian Tiger mosquito.
There are two strains of Zika virus, African and Asian. The strain causing the current outbreaks in South America is the Asian strain.
Zika virus may be transmitted by infectious mosquito bites, infection of unborn children by their infected mothers, blood transfusions from asymptomatic, Zika infected blood donors, and by sexual transmission of Zika virus in infected sperm.
The virus produces a range of symptoms including:
The virus is also being correlated with an increase in the birth defect microcephaly and the Guillain-Barre syndrome. Current research is showing that pregnant women that are bit by an infected mosquito within the first trimester are at highest risk. With the exception of the microcephaly and Guillain-Barre syndrome; the Zika virus in itself is not fatal and produces relatively mild symptoms. Also, only about 20% of those afflicted with the virus are symptomatic; the remaining 80% are asymptomatic.