Definition of Zika virus

Zika virus: a Flavivirus related to dengue fever, West Nile, yellow fever, and Japanese encephalitis viruses (Flaviviridae). The Zika virus is transmitted to humans by Aedes mosquito bites and leads to an illness that lasts a few days to a week. Typical signs and symptoms of Zika virus infection include fever, rash, joint pain, and conjunctivitis (redness of the eyes). The illness is usually mild, and people may not be aware they have become infected. The infection also can be spread by sexual contact with an infected man, and the virus can be passed from a pregnant women to her fetus. When pregnant women become infected, the viral infection has been linked to birth defects (microcephaly, or a small head and small brain) in newborns. There is no vaccine available against Zika virus.