There has been some discussion amongst public health and infectious disease experts about the potential of Zika virus to spread through the sexual route, especially if the infected source patient does not suffer from hematospermia. In a series of cases published by the U.S. Centers for Disease Control and Prevention (CDC), in their Morbidity and Mortality Weekly Report (MMWR), a case series of sexually transmitted ZIKV disease are documented. Image credits: HIV Plus Magazine
The report states:
During February 6–22, 2016, two confirmed and four probable cases of Zika virus sexual transmission were reported to CDC by health officials from multiple states. Median patient age was 22.5 years (range = 19–55 years), and several women were pregnant. In all cases where type of sexual contact was documented, the contact included condomless vaginal intercourse and occurred when the male partner was symptomatic or shortly after symptoms resolved. Three illustrative cases are presented.
Case 1. In mid-January, immediately after returning to the United States from a 10-day trip to the Caribbean, a man developed illness with fever, arthralgia, bilateral conjunctivitis, and a maculopapular, pruritic rash. The illness lasted 6 days. No hematospermia or prostatitis was noted. On the 1st or 2nd second day of illness, he had condomless vaginal intercourse with his female partner. The woman developed a febrile illness 13–14 days after sexual contact, with rash, conjunctivitis, and myalgia. Zika virus RNA was detected in the woman’s serum by reverse transcription-polymerase chain reaction (RT-PCR) assay. Test results for the man are pending. The woman had no recent history of travel outside of the continental United States, and local mosquito-borne transmission of Zika virus was not considered possible; the vectors that transmit the virus are not present or active where she lives, based on the location and current temperatures.
Case 2. In late January, a man returned to the United States after a 4-week trip to Central America. The same day, he developed fever, arthralgia, generalized pruritus, myalgia, and eye discomfort. He had condomless vaginal intercourse with his female partner several times during the following 8 days. Ten days after the man’s return, his female partner developed fever, pruritic rash, arthralgia, eye pain, photophobia, headache, vomiting, and myalgia. Zika virus infection in the woman was confirmed by RT-PCR testing of serum. Serum collected from the man tested positive for Zika virus immunoglobulin M (IgM) antibodies; confirmation is pending. The woman had no recent history of travel outside the continental United States, and current local mosquito-borne transmission of Zika virus was not considered possible where she lives.
Case 3. In mid-January, a man returned from Central America with fever, rash, arthralgia, conjunctivitis, headache, and myalgia. His symptoms began 3 days earlier and persisted until approximately 3 days after his return. On the day of his return, he had sexual contact with his female partner. Ten days later, the woman developed rash, arthralgia, conjunctivitis, and myalgia. Serum collected from the woman tested positive for Zika virus IgM; confirmation is pending. Test results for the man are pending. The woman had no recent history of travel outside of the continental United States, and current local mosquito-borne transmission of Zika virus was not considered possible where she lives.
The CDC had released interim guidelines about the possibility of sexual transmission of ZIKV disease on 5th February, which was then further updated on 23rd February, based on 14 reports of suspected sexually transmitted cases of ZIKV disease in the intervening period.
This report adds a vital bit to the understanding of a disease which has been declared to be a public health emergency of international concern (PHEIC) mainly because of the poor understanding we have of the entire gamut of effects of infection with ZIKV. The report adds the cautious message:
Men who reside in or have traveled to an area of ongoing Zika virus transmission who have a pregnant partner should abstain from sexual activity or consistently and correctly use condoms during sex (i.e., vaginal intercourse, anal intercourse, or fellatio) with their pregnant partner for the duration of the pregnancy.
Hills SL, Russell K, Hennessey M, et al. Transmission of Zika Virus Through Sexual Contact with Travelers to Areas of Ongoing Transmission — Continental United States, 2016. MMWR Morb Mortal Wkly Rep 2016;65:215–216. DOI: http://dx.doi.org/10.15585/mmwr.mm6508e2