Zika Virus Transmission From Woman to Man Reported for First Time, CDC Says

— -- The Zika virus has been documented for the first time to have been transmitted from a woman to a man through sexual contact, according to a new report from the U.S. Centers for Disease Control and Prevention.

While the Zika virus has been known to spread through sexual contact, all previously reported cases occurred from an infected male to his partner. While the symptoms of the virus usually resolve in about a week, the virus has been found to survive in semen for weeks after infection, leading to additional concerns about sexual transmission of the virus.

The CDC has issued guidelines focusing on stopping men from transmitting the virus through sexual contact. Men with pregnant partners are advised to use barrier contraception during the duration of the pregnancy to ensure their partner is not infected with the virus, which has been shown to potentially cause birth defects, including microcephaly, characterized by an abnormally small head and brain, leading to serious developmental delays.

This new kind of transmission could affect guidelines about stopping the sexually transmitted Zika infections.

The mosquito-borne Zika virus usually results in mild symptoms, including fever, rash and fatigue, but it has been connected with microcephaly in Brazil. Recent studies have suggested that this birth defect is just one of multiple neurological defects that can occur when a fetus is exposed to the virus. Current strains of the virus have been found to specifically target and destroy brain and nervous system tissue.

The CDC has recommended that pregnant women avoid travel to areas with ongoing Zika transmission.