State health officials confirmed California's first case of sexually-transmitted Zika virus Friday. A San Diego County woman was infected through sexual contact with her partner, who recently returned from abroad, health officials said.
The partner — a San Diego County man — had been to Colombia in January, one of the countries where the virus is prevalent, according to a statement from San Diego's department of health and human services. Shortly after, he came down with a fever and rash that lasted a total of 10 days. During that time he had sex with his partner, who came down with a fever and rash two days later, the statement said.
The woman was not pregnant and had not been traveling out of the country. She and her partner have since fully recovered, the department said.
Zika virus has been linked with birth defects in the infants of pregnant women who have the virus. Those defects include microcephaly, which is when a baby is born with a smaller than usual head due to neurological complications during pregnancy.
The virus is mostly spread by mosquitos, although the World Health Organization announced Thursday that transmission through sex is likely more common than thought.
"To the best of our knowledge, Zika virus can only be sexually transmitted from a man to his female partner," Vicki Kramer, chief of the state department of public health's vector-borne disease section, told KPCC.
The Centers for Disease Control and Prevention recommends that men who have traveled to an area with Zika activity should "consistently and correctly use condoms during sex ... or abstain from sexual activity" on their return. The cautions apply to vaginal, anal or oral sex.
"The science is not clear on how long the risk should be avoided," the CDC said. "Research is now underway to answer this question as soon as possible. If you are trying to get pregnant, you may consider testing in discussion with your healthcare provider."
Most people infected with Zika virus will not develop symptoms, and if symptoms do develop, they are usually mild and include fever, rash, joint pain and eye redness, the state health department said.
"If you have returned from an affected country and you have fever with rash, joint pain, and eye redness within two weeks, or any other symptoms following your return, please contact your medical provider and tell the doctor where you have traveled," the health department's announcement said. "While there is no specific treatment for Zika virus disease, the best recommendations are supportive care, rest, fluids and medications for relief of fever."
The Zika virus is primarily transmitted to people by mosquitoes known as Aedes aegypti (yellow fever mosquito) and Aedes albopictus (Asian tiger mosquito), which are the same type of mosquitoes that transmit dengue and chikungunya viruses. These types of mosquitoes have been detected in 12 California counties. To date, there have been 22 travel-associated cases of Zika virus reported in California in 2015-2016. No local mosquito-borne transmission of Zika virus has been reported in the state, the health department said.
For more information on what you need to know about Zika virus, see our FAQ.
Correction: An earlier version of this post erroneously referred to this Zika case as the first in California. There have been several others in the state, including in L.A. County. It also misspelled the last name of Vicki Kramer.