Woman found to spread Zika through sex for 1st time

“The New York City report of female-to-male sexual transmission of Zika virus infection is the first documented case of sexual transmission of Zika from a woman to her sex partner and adds to the growing body of knowledge about the sexual transmission of Zika”, the CDC said.

In Zika’s case, that process will take a decade or more, the authors of the new report project.

The Zika virus is carried by the Aedes aegypti mosquito, but the team cautioned any large-scale government programmes to target the mosquitoes may have limited impact.

The woman’s male partner, also in his 20s, developed fever, rash, joint pain and red eyes a week after having sex with her. He went to the same primary care provider who had diagnosed Zika infection in the woman.

Evidence from other outbreaks of mosquito-borne illness has suggested that battling Zika by reducing mosquito populations could slow the population’s path to herd immunity, wrote Ferguson and his colleagues. “This the first case that we’re aware of, anywhere”. The U.S. has reported a total of 4,222 cases in both states and territories.

“I’m happy to say patients really have been quite receptive about volunteering their specimens”, said Dr. Paul Mead, the senior epidemiologist at the CDC who is running the study. The woman was not pregnant.

However, Professor Ferguson highlighted there are still many questions to answer about Zika – and therefore many caveats to making predictions: “In a worst case scenario Zika would become endemic in Latin America in the long-term, which would mean smaller, frequent outbreaks”. Since 2014, more than 1,400 babies with grievous birth defects have been born to women in Brazil who were infected with Zika during their pregnancies. Overall, the city has identified 309 cases of the virus, all ultimately springing from overseas travel. The CDC now recommends that pregnant women whose sexual partners are female take the same precautions.

But, according to Sunil Sood, MD, Chief of Pediatric Infectious Diseases at Southside Hospital, the CDC is likely now to revise its guidance to include female-to-male transmission and non-pregnant women. Osterholm pointed to the four-year spread across the United States of the West Nile virus – which is in the same family of viruses as Zika. If they have symptoms, they should practice safe-sex for at least two months.

CDC said it is updating recommendations for sexually active people in which the couple is not pregnant or concerned about pregnancy and for people who want to reduce personal risk of Zika infection through sex.

Doctors knew that the Zika virus could be sexually transmitted, but until now they’d only seen cases where an infected man passed it to his partner.

The doctor suspected sexual transmission of the virus and sent the man’s urine samples to be tested, confirming the presence of the virus.

In the NY case, for example, several factors lined up to allow the disease to spread. And the man was uncircumcised, and uncircumcised men are considered at higher risk of catching sexually transmitted diseases.