Suspected female-to-male sexual transmission of Zika virus in New York City
A recent report describes the detection of Zika virus RNA from a woman’s cervical mucous up to 11 days after onset of symptoms which is in line with the current observation of female-to-male Zika virus transmission.
On 15 July, the Centers for Disease Control and Prevention (CDC) in the USA reported in its Morbidity and Mortality Weekly Report a suspected female-to-male sexual transmission of Zika virus in New York City [1].
A non-pregnant woman reported one single event of condomless vaginal intercourse with a male partner the day she returned to New York City (day 0) from travel to an area with ongoing Zika virus transmission. The woman had mild unspecific symptoms of Zika virus infection from the previous day; symptoms became Zika-specific from the day after (day 1) when the woman also began menses. The woman later had Zika infection confirmed by real-time reverse transcription–polymerase chain reaction (rRT-PCR) in both serum and urine.
The male partner experienced symptoms of Zika virus infection on day 6. Zika virus infection was confirmed by rRT-PCR both on blood and urine specimens obtained on day 9. The man reported no travel outside the United States during the year before his illness, not engaging in oral or anal intercourse with his partner, no other recent sexual partners and no mosquito bites within the week preceding his illness.
The event supports female-to-male Zika virus transmission through condomless vaginal intercourse through virus present in either vaginal fluids or menstrual blood transmitted during exposure to her male partner’s urethral mucosa or undetected abrasions on his penis.
Comment from ECDC, 18 July 2016
This is the first report of a suspected female-to-male sexual transmission of Zika virus. A recent report describes the detection of Zika virus RNA from a woman’s cervical mucous up to 11 days after onset of symptoms [2] which is in line with the current observation of female-to-male Zika virus transmission [1]. Much is yet to be learned about the timing and persistence of Zika virus in the female genital tract and vaginal fluid and the likelihood of transmission of the Zika virus from a female to her sex-partner.
The current ECDC options for response to prevent sexual transmission of Zika virus state that travellers returning from areas with ongoing Zika virus transmission should be advised to use a condom for at least eight weeks after returning, in order to reduce the potential risk of onward sexual transmission. If before or during that period symptoms of Zika virus infection occur, men should use condoms or consider abstinence for at least six months [3]. These options remain valid and will be updated when more information becomes available.
- Davidson A, Slavinski S, Komoto K, Rakeman J, Weiss D. Suspected Female-to-Male Sexual Transmission of Zika Virus — New York City, 2016. MMWR Morb Mortal Wkly Rep. Atlanta: CDC; 2016. Available from: http://www.cdc.gov/mmwr/volumes/65/wr/mm6528e2.htm.
- Prisant N, Bujan L, Benichou H, Hayot P-H, Pavili L, Lurel S, et al. Zika virus in the female genital tract. Lancet Infect Dis. In press 2016. Available from: http://dx.doi.org/10.1016/S1473-3099(16)30193-1
- European Centre for Disease Prevention and Control. Rapid risk assessment. Zika virus disease epidemic. Seventh update, 8 July 2016. Stockholm: ECDC; 2016.