The chasm between public health and reproductive research: what history tells us about Zika virus

Irina Burd, Diane Griffin

Zika transmission from mother to fetus and its possible sexual transmission have become a media focus in the past months as a major public health concern. While mother-to-fetus transmission, fetal neurologic manifestations or sexual transmission have never been documented for this virus before, other viruses that belong to the same family are very well known to reproductive health workers, clinicians, and researchers. As a member of Flaviviridae family, including hepatitis C and bovine viral diarrhea virus (BVDV), Zika's pathogenesis may have some parallels with these infections which may pose future questions for public health and research. Vertical transmission of hepatitis C virus from mother to child is known to occur in up to 10 % of pregnancies. BVDV, a member of Pestivirus genus of Flaviviridae family is not known to be transmitted to humans but is known for its vertical transmission in cattle. BVDV infection at different stages of gestation may lead to a spectrum of adverse pregnancy outcomes, including pregnancy loss and neurologic manifestations (including deformations such as hydrocephalus and microcephaly) in the offspring. Similar to hepatitis C, which is a virus of Hepacivirus genus, BVDV is capable of persistent infection, meaning that virus may stay in mother and future generations of calves may be infected as well, which may, in turn, result in persistence of infection in offspring. Would this be a case with Zika virus? Along with mother-to-fetus transmission, sexual transmission is a concerning implication for Zika virus. Would woman become a persistent career or male be able to persistently carry virus with its sperm is yet unknown; yet, there is a concern for the reservoir of infection. Animal models of the disease are urgently needed not only to demonstrate the mother-to-fetus transmission and confirm the fetal neurologic manifestations but also to address the effects of virus on life-long host's immunity and reproductive health. Along those lines, women desiring pregnancies who are identified to travel, have a partner traveling to, or living in the areas of Zika infections should be encouraged to have a preconception consultation with maternal-fetal medicine.