Spondweni virus causes fetal harm in Ifnar1-/- mice and is transmitted by Aedes aegypti mosquitoes

Virology. 2020 Aug:547:35-46. doi: 10.1016/j.virol.2020.05.005. Epub 2020 May 24.

Abstract

Spondweni virus (SPONV) is the most closely related known flavivirus to Zika virus (ZIKV). Its pathogenic potential and vector specificity have not been well defined. SPONV has been found predominantly in Africa, but was recently detected in a pool of Culex quinquefasciatus mosquitoes in Haiti. Here we show that SPONV can cause significant fetal harm, including demise, comparable to ZIKV, in a mouse model of vertical transmission. Following maternal inoculation, we detected infectious SPONV in placentas and fetuses, along with significant fetal and placental histopathology, together suggesting vertical transmission. To test vector competence, we exposed Aedes aegypti and Culex quinquefasciatus mosquitoes to SPONV-infected bloodmeals. Aedes aegypti could efficiently transmit SPONV, whereas Culex quinquefasciatus could not. Our results suggest that SPONV has the same features that made ZIKV a public health risk.

Keywords: Aedes aegypti; Arbovirus; Congenital zika syndrome; Flavivirus; Spondweni virus; Vector competence; Zika virus.

Publication types

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

MeSH terms

  • Aedes / physiology
  • Aedes / virology*
  • Animals
  • Disease Models, Animal
  • Female
  • Flavivirus / genetics
  • Flavivirus / physiology*
  • Flavivirus Infections / genetics
  • Flavivirus Infections / metabolism
  • Flavivirus Infections / mortality
  • Flavivirus Infections / virology*
  • Humans
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mosquito Vectors / physiology
  • Mosquito Vectors / virology*
  • Receptor, Interferon alpha-beta / deficiency
  • Receptor, Interferon alpha-beta / genetics*

Substances

  • Ifnar1 protein, mouse
  • Receptor, Interferon alpha-beta