The Zika virus can be passed through vaginal sex, anal sex—and possibly oral sex, scientists now say based on a single case in France. A 46-year-old man who developed Zika symptoms during a two-month stay in Brazil returned home to Paris in February, then had unprotected vaginal sex without ejaculation and oral sex with ejaculation with a 24-year-old partner on seven occasions between Feb. 11 and Feb. 20, the New York Times reports via a letter to the New England Journal of Medicine. Three days later, both tested positive for Zika. High levels of the virus were found in the man's semen and urine, but not in his blood or saliva, while the virus was detected in the woman's urine and saliva, and antibodies to Zika were found in her blood. A vaginal swab found no signs of the virus.
"We cannot rule out the possibility that transmission occurred not through semen but through other biologic fluids, such as pre-ejaculate secretions or saliva exchanged through deep kissing," the scientists acknowledged in their letter. A CDC epidemiologist says he's "not particularly surprised" by the case. "I don't think this changes anything, but it shows you how elaborate the number of avenues of possible transmission can be," the head of preventive medicine at Vanderbilt University Medical School tells the Times. The WHO recently revised its guidelines, noting those who visit a Zika-infected country should refrain from unprotected sex for eight weeks, rather than four, per CNN. (Read more Zika virus stories.)