Read condition-specific symptoms and clinical context for Zika virus. A mosquito-borne virus that is usually mild but serious in pregnancy.
WHO describes Zika as a mosquito-borne virus spread primarily by Aedes mosquitoes that bite mostly during the day, with most infected people developing no symptoms. Its documented importance is infection during pregnancy, which can cause microcephaly and other congenital malformations, and an association with Guillain-Barré syndrome in adults and children.
CDC states many infected people have no symptoms or only mild ones, and that symptoms usually last several days to a week. WHO puts onset at 3–14 days after infection.
Possible symptoms: Fever; Rash; Headache; Joint pain; Red eyes (conjunctivitis); Muscle pain.
CDC notes Zika causes symptoms similar to other mosquito-borne illnesses such as dengue and chikungunya, that people usually do not become sick enough to go to hospital, and that many people may not realise they were infected. Rarely, Zika may cause Guillain-Barré syndrome or severe disease affecting the brain.
CDC and WHO describe outcomes documented after Zika infection during pregnancy. These are reported outcomes across affected populations, not a prediction for any pregnancy.
Possible symptoms: Microcephaly (smaller than normal head size); Other congenital malformations; Preterm birth; Miscarriage or fetal loss; Stillbirth.
WHO states no vaccine is yet available for the prevention or treatment of Zika virus infection, and that sexual transmission was confirmed as an alternative route. Questions about an individual pregnancy belong with a clinician.
Source check: 2026-09-19. Educational content; independent scientific review remains pending.