Zika

WHAT CALIFORNIANS NEED TO KNOW

Zika virus is transmitted to people primarily through the bite of infected Aedes aegypti mosquitoes (yellow fever mosquitoes) or Aedes albopictus mosquitoes (Asian tiger mosquitoes). These mosquitoes are not native to California. However, since 2011 they have been detected in several California counties. An Aedes mosquito can only transmit Zika virus after it bites a person who has this virus in their blood. To date there has been no local mosquito-borne transmission of Zika virus in California.

Thus far in California, Zika virus infections have been documented only in people who were infected while traveling to areas with ongoing Zika transmission, through sexual contact with an infected traveler, or through maternal-fetal transmission during pregnancy. Zika virus during pregnancy can cause microcephaly and other severe brain defects in infants. Additionally, there is an association between Zika and Guillain-Barré Syndrome, a disease affecting the nervous system.

Monthly Update on Zika Cases in California

On the 1st Friday of the month, CDPH updates the number of travel-associated Zika infections in California residents in 2015-2019, including the number of infections reported this month.

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News and Alerts

Countries and Territories with Active Zika Virus Transmission

The CDC maintains a list of countries and territories with reported mosquito-borne Zika virus transmission. The list does not include places that have only reported travel-associated cases or a history of past Zika transmission.

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Zika Information

Map and City List of Aedes
Mosquitoes in CA

On the 1st Friday of the month, CDPH updates the location of infestations of Aedes aegypti and Aedes albopictus mosquitoes detection sites by County/City in California.

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