The primary concern about Zika infection is the virus's threat to pregnancies, and health officials have issued cautions to pregnant women who have a male sex partner who may have been infected.
About 20 percent of infected people show symptoms, most recovering within several days from fever, joint pain or other mild ailments.
The day the woman returned to New York City, she had sex with her male partner without using a condom.
The virus, which causes birth defects, has been reported in dozens of countries, mostly concentrated in South and Central America. Before realizing she had the virus, she'd had unprotected sex with the man. He saw the same doctor as her, who suspected she'd passed the illness to him sexually; the city's health department confirmed that suspicion.
Her male partner, who had not traveled to a Zika-hit region, developed symptoms of Zika a week later, and a test revealed he had also contracted the virus. The finding came after New York City DOH officials reported their first case. It is now recommending that pregnant females whose partners have traveled to a place where the Zika virus is spreading should make sure condoms are used or abstain from sex for the duration of the pregnancy. The report described the transmission of virus present in either vaginal fluids or menstrual blood during exposure to her male partner's urethral mucosa or undetected abrasions on his penis. Both people have been diagnosed with Zika.
Recent evidence of sexual transmission of the virus from men to women and men to men is also being studied.
Previous studies and reports have suggested that the Zika virus can remain in vaginal fluids while not showing presence in urine or blood tests.
Research into the exact risks posed by maternal Zika infection is ongoing, according to health officials.
Until now, experts were aware only of cases in which men spread the virus to their partners during sex, as well as transmission by mosquito bites. Before the case was reported, researchers thought that only male-to-female and male-to-male sexual Zika transmission was possible.
Just the same, locals are urged to take precautions by preventing mosquito breeding and protecting themselves from bites, Doyle said.
The woman developed fever, fatigue, a rash and body aches the next day, and sought treatment. And the man was uncircumcised, and uncircumcised men are considered at higher risk of catching sexually transmitted diseases.