The first case of Zika virus in the Bay Area was confirmed Wednesday by Napa County health officials.
In a statement, the Napa County Public Health Division said the California Department of Public Health has confirmed "a pregnant woman who traveled to Central America" contracted the virus, but she "is not showing symptoms of Zika virus infection at this time."
Health officials, who are not identifying the woman, say the virus is not a public health threat.
"There is no active transmission of Zika virus in Napa County, and the two kinds of mosquitos that transmit the virus have not been found here," said Dr. Karen Relucio, Napa County Health Officer. "Anyone who is planning to travel to a country with active Zika virus transmission should consult with their healthcare provider before leaving, especially if they are pregnant or are considering becoming pregnant."
This is not the first case of the Zika virus in California. Other cases have been confirmed in Los Angeles, San Diego and Yolo counties.
Napa County health officials say they're working with local healthcare providers to "test for cases of Zika virus among pregnant women who have traveled to countries with Zika virus transmission or who have sexual partner(s) that have traveled to countries with Zika virus."
Officials in Napa County said they expect to confirm more cases as testing for continues. They are advising women who are pregnant or who may become pregnant to avoid traveling to areas where the virus is prevalent and to avoid unprotected sex with anyone who has traveled to areas with Zika.
Nationwide, there are more than 10 reported cases of Zika virus involving pregnant women, but locally, Napa County officials stressed the latest patient is no longer showing symptoms of the virus and health officials say they do not see any evidence that this virus was transmitted locally.
The Zika virus – spread mainly by mosquito bites – is epidemic in Latin America and the Caribbean. The virus causes mild illness or no symptoms in most people. But in Brazil, officials are investigating a possible link to babies born with unusually small heads, a rare birth defect called microcephaly that can signal underlying brain damage.
According to the Centers for Disease Control and Prevention , there have been no reported mosquito-transmitted cases of Zika in the U.S.