[Viruses and bats: rabies and Lyssavirus].

Abstract

Recent emerging zoonoses (hemorrhagic fevers due to Ebola or Marburg virus, encephalitis due to Nipah virus, severe acute respiratory syndrome due to SRAS virus...) outline the potential of bats as vectors for transmission of infectious disease to humans. Such a potential is already known for rabies encephalitis since seven out of the eight genotypes of Lyssavirus are transmitted by bats. In addition, phylogenetic reconstructions indicate that Lyssavirus have evolved in chiropters before their emergence in carnivores. Nevertheless, carnivores remain the most critical vectors for public health, in particular dogs that are originating 55.000 rabies deaths per year, essentially in developing countries. Rabies control in carnivores by parenteral (dog) or oral (wild carnivores) vaccination is efficacious and campaigns start to be more widely applied. On the other hand, rabies control in bat still remains non realistic, particularly as the pathogenicity of bat Lyssavirus for bats is still under debate, suggesting that a "diplomatic relationship" between partners would have arisen from a long term cohabitation. While comparing the interactions that humans and bats establish with Lyssavirus, scientists try to understand the molecular basis ofpathogenicity in man, a indispensable prerequisite to identify antiviral targets in a perspective of therapy.