Determinants of Arbovirus Vertical Transmission in Mosquitoes

PLoS Pathog. 2016 May 12;12(5):e1005548. doi: 10.1371/journal.ppat.1005548. eCollection 2016 May.

Abstract

Vertical transmission (VT) and horizontal transmission (HT) of pathogens refer to parental and non-parental chains of host-to-host transmission. Combining HT with VT enlarges considerably the range of ecological conditions in which a pathogen can persist, but the factors governing the relative frequency of each transmission mode are poorly understood for pathogens with mixed-mode transmission. Elucidating these factors is particularly important for understanding the epidemiology of arthropod-borne viruses (arboviruses) of public health significance. Arboviruses are primarily maintained by HT between arthropod vectors and vertebrate hosts in nature, but are occasionally transmitted vertically in the vector population from an infected female to her offspring, which is a proposed maintenance mechanism during adverse conditions for HT. Here, we review over a century of published primary literature on natural and experimental VT, which we previously assembled into large databases, to identify biological factors associated with the efficiency of arbovirus VT in mosquito vectors. Using a robust statistical framework, we highlight a suite of environmental, taxonomic, and physiological predictors of arbovirus VT. These novel insights contribute to refine our understanding of strategies employed by arboviruses to persist in the environment and cause substantial public health concern. They also provide hypotheses on the biological processes underlying the relative VT frequency for pathogens with mixed-mode transmission that can be tested empirically.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arbovirus Infections / transmission*
  • Arboviruses
  • Culicidae / virology*
  • Humans
  • Infectious Disease Transmission, Vertical*
  • Mosquito Vectors / virology*

Grant support

SL was supported by a doctoral fellowship from University Pierre and Marie Curie. LL received funding from the French Government's Investissement d'Avenir program, Laboratoire d'Excellence Integrative Biology of Emerging Infectious Diseases (grant ANR-10-LABX-62-IBEID) and from the City of Paris Emergence(s) program in Biomedical Research. The research leading to these results has received funding from the European Commission Seventh Framework Program [FP7/2007-2013] for the DENFREE project under Grant Agreement n°282 378. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.