The flavivirus is a species-rich family of RNA viruses that occur in many tropical and subtropical countries and is transmitted mainly by mosquitoes or ticks. The genus contains more than 89 virus species with 73 serotypes. . Flaviviruses have spherically enveloped virions with a diameter of 40-60 nm.
The most important diseases derived from the flavivirus strain are yellow fever virus, Japanese encephalitis virus, TBE virus (early summer meningoencephalitis), Zika virus and Dengue Fever.

The Zika virus was first isolated in 1947 from a rhesus monkey captured specifically to find the yellow fever virus and named after the place where it was first isolated. According to WHO (“Public Health Emergency of International Proportions”, February 1,.2016), in up to 20% of cases, infection of a pregnant woman with the zika virus can cause damage to the brain neurons in the foetus. If the children survive, severe malformations sometimes occur.