SAN FRANCISCO (CBS SF) -- Two more San Francisco residents have tested positive for Zika virus, bringing the total number of people infected in the city to 10, the San Francisco Department of Public Health announced Friday.
News of the recent infections comes just after the California Department of Public Health reported Thursday that two infants suffering from Zika-related microcephaly were born in California to mothers who contracted the virus outside the country.
Although mosquitoes capable of carrying the virus have been discovered in at least 12 California counties, there is no evidence the mosquitoes are transmitting Zika in the state, CDPH officials said.
All San Francisco residents who have contracted the virus did so while traveling in countries where Zika is circulating, according to SFDPH officials.
The first case of Zika in San Francisco was reported on March 3, followed by a second case reported on April 22. Six cases were then reported last month.
Zika virus is spread through mosquito bites and can generally cause mild symptoms in patients, such as fever, joint pain, rash and red eyes. Places where the virus is currently circulating include most of Latin America, the Caribbean and the Pacific Islands.
Pregnant women are most at-risk for contracting the virus, as Zika is known to cause microcephaly, a condition that causes babies to be born with abnormally small heads.
"This is a sobering reminder for Californians that Zika can cause serious harm to a developing fetus," CDPH Director and State Health Officer Dr. Karen Smith said. "Zika virus can also be transmitted to sexual partners by both males and females. Both men and women of child-bearing age should take precautions if they have recently traveled, or plan to travel, to a location where Zika is spreading."
The CDPH said it would provide assistance to the families with infants born with microcephaly and other Zika-related birth defects.
Additionally, infants born to mothers with confirmed infections will be monitored for at least one year, according to CDPH officials.
Although the two recent cases of microcephaly are reported to be the first in the state, at least 21 infections have been confirmed in pregnant California residents, according to the CDPH.
Currently, there is no vaccine or treatment for Zika, other than supportive care, rest, fluids and fever relief, CDPH officials said.
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