First female to male Zika case reported

New York City’s health department has reported the first female-to-male transmission of the Zika virus, which is most typically spread by the bite of an infected mosquito.

Transmission of the virus occurred on the day that a woman in her 20s returned to New York from an area with active Zika transmission and had a single event of unprotected sex with a male partner.

The man had not travelled outside the United States in the previous year.

The woman developed fever, fatigue, a rash, and body aches the next day and sought treatment. Health department officials then confirmed her infection.

When her male partner developed symptoms seven days later and sought treatment from the same caregiver, he too was diagnosed with Zika.

Health officials from New York, who reported the case in the US Centres for Disease Control and Prevention’s weekly report on death and disease, said the timing and sequence of events support female-to-male Zika virus transmission through unprotected vaginal sex.

The CDC said it recommends that all pregnant women who have a sex partner who has travelled to or resides in an area with Zika use barrier methods every time they have sex, or they should not have sex during the pregnancy.

Though no case of woman-to-woman Zika transmission has been reported, these recommendations now also apply to female sex partners of pregnant women.

US health officials have concluded that Zika infections in pregnant women can cause microcephaly, a birth defect marked by small head size that can lead to severe developmental problems.

The World Health Organisation said there is strong scientific consensus that Zika can also cause Guillain-Barre, a rare neurological syndrome that causes temporary paralysis in adults.