ZIKA virus, human genital tract and sexual transmission

Zika virus had recently emerged in Asia and in Americas and was responsible of several human diseases. While the infection typically causes unapparent or benign illness, drastic effects of infection in pregnant women resulting on fetus development and births defects as well as neuro pathologies in infected adults were described. Consequently, WHO designated the Zika virus epidemic "a public health emergency of international concern" from April to November 2016. Zika virus is transmitted by mosquitoes but sexual transmissions were reported. In this context, the links between Zika virus and male and female genital tracts must be investigated. We report and discuss herein the results of the prospective study Ziksperm dealing with semen and Zika virus in man, and, the results of transversal studies about female genital tract and Zika virus in human. In men we demonstrated that Zika virus was found in semen until 120 days after acute infection and we described three patient patterns according to ZIKA viral shedding in semen: non-shedding patients, seminal shedders with concomitant blood, urines shedding, long-term seminal shedding without blood and urines shedding. Moreover, we found competent virus in a pure population of spermatozoa. Acute Zika infection resulted in semen and reproductive modifications which returned to normal status 120 days after acute infection. In women, we found Zika virus in vaginal and endocervical swabs. The duration of Zika virus shedding in female genital tract was shorter than in male genital tract but shedding in genital tract was described although that blood and urines viral load were negative. These finding are important in order to understand the consequences of Zika virus on reproductive function, to evaluate the risk of sexual transmission, and to help physicians to counsel infected patients and public health specialists to make policy recommendations.