Alameda County health officials said 10 residents have contracted the Zika virus by traveling to areas where the disease is being transmitted by mosquitoes.
That's up from one case reported in March.
County health officials said the risk of the virus being
transmitted locally is extremely low because the Aedes aegypti and Aedes albopictus mosquitoes, which transmit the virus, are not native to the Bay Area and have not established populations here.
But the virus can be transmitted during sex and pregnant women can transmit the disease to their fetuses.
An infant born with the virus may be born with a birth defect such as microcephaly, which causes children to be born with unusually small heads.
Health officials encourage women who are pregnant or thinking
about getting pregnant to delay or cancel travel to an area where mosquitoes are transmitting the virus.
Otherwise, travelers should take precautions such as using
mosquito repellents, mosquito nets and clothing that covers as much of the body as possible.
As of Wednesday, almost all of the 1,825 people with the virus
contracted it by traveling to an area where mosquitoes are transmitting the virus or through sex with a person who had traveled to one of those areas, county health officials said.
As of Friday, 134 cases of Zika have been reported in California.
Twenty-three of those people were pregnant woman and two babies born in California have a birth defect linked to the virus.
One person in California contracted the virus through sex.