One of the two California infants with a Zika-related birth defect was born in Alameda County, a county official confirmed on Friday.
The Alameda County Public Health Department declined to release any other information about the infant or the mother.
The California Department of Public Health on Thursday disclosed that two babies have been born in the state with a severe birth defect known as microcephaly.
It’s a condition in which an infant has a smaller-than-normal head. It occurs when exposure to a chemical or virus impairs brain development early in pregnancy.
Zika is one of the viruses associated with microcephaly. Mothers of the two infants contracted the virus while traveling in countries where Zika is common, state public health officer Karen Smith said.
KGO TV first reported late Thursday that one of the babies had been born several months ago at Alta Bates Hospital in Berkeley.
One of the California mothers has returned with her affected infant to her home country, Smith said. State officials would not identify that country but said Zika is actively transmitted there. It wasn’t clear whether the Alameda County woman was the one who had left the U.S.
The two primary mosquito species capable of transmitting Zika – Aedes aegypti and Aedes albopictus – have been found in 12 California counties.
The mosquitoes have been found as far north as Hayward and Menlo Park in the Bay Area and in Central Valley cities such as Madera, Fresno and Clovis.
The virus can also be spread through sexual contact.
The state has not identified any cases of a person becoming infected with the virus from a mosquito in California.
The state has reported 114 cases of travel-associated Zika infections as of July 29 in 22 California counties. Last week, Sacramento County reported its first case of Zika virus, also transmitted during travel.