Vaginal Exposure to Zika Virus during Pregnancy Leads to Fetal Brain Infection

Cell. 2016 Aug 25;166(5):1247-1256.e4. doi: 10.1016/j.cell.2016.08.004.


Zika virus (ZIKV) can be transmitted sexually between humans. However, it is unknown whether ZIKV replicates in the vagina and impacts the unborn fetus. Here, we establish a mouse model of vaginal ZIKV infection and demonstrate that, unlike other routes, ZIKV replicates within the genital mucosa even in wild-type (WT) mice. Mice lacking RNA sensors or transcription factors IRF3 and IRF7 resulted in higher levels of local viral replication. Furthermore, mice lacking the type I interferon (IFN) receptor (IFNAR) became viremic and died of infection after a high-dose vaginal ZIKV challenge. Notably, vaginal infection of pregnant dams during early pregnancy led to fetal growth restriction and infection of the fetal brain in WT mice. This was exacerbated in mice deficient in IFN pathways, leading to abortion. Our study highlights the vaginal tract as a highly susceptible site of ZIKV replication and illustrates the dire disease consequences during pregnancy.

Keywords: antiviral defense; female reproductive tract; flavivirus; innate immunity; mucosal immunity; pattern recognition receptors; sexually transmitted infections; type I interferons.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abortion, Habitual / virology
  • Animals
  • Brain / virology*
  • Brain Diseases / immunology
  • Brain Diseases / virology*
  • Disease Models, Animal
  • Female
  • Fetal Growth Retardation / immunology
  • Fetal Growth Retardation / virology*
  • Interferon Regulatory Factor-3 / genetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Mutant Strains
  • Pregnancy
  • Pregnancy Complications, Infectious / immunology
  • Pregnancy Complications, Infectious / virology*
  • Receptor, Interferon alpha-beta / genetics
  • Vagina / virology*
  • Virus Replication*
  • Zika Virus / physiology*
  • Zika Virus Infection / transmission*


  • Interferon Regulatory Factor-3
  • Receptor, Interferon alpha-beta