Bioecological Drivers of Rabies Virus Circulation in a Neotropical Bat Community

International audienceIntroductionIn addition to the commonly accepted importance of the vampire bat in the maintenanceand transmission of the rabies virus (RABV) in South America, RABV infection of other speciesis widely evidenced, challenging their role in the viral cycle.Methodology / Principles findingsTo identify the bioecological drivers of RABV circulation in neotropical bat communities, weconducted a molecular and serological survey on almost 1,000 bats from 30 species, and a4-year longitudinal survey in two colonies of vampire bats in French Guiana. RABV wasmolecularly detected in a common vampire and in a frugivorous bat. The sequences correspondedto haematophagous bat-related strains and were close to viruses circulating in theBrazilian Amazon region. Species’ seroprevalence ranged from 0 to 20%, and the risk ofseropositivity was higher in bats with a haematophagous diet, living in monospecific coloniesand in dense forests. The longitudinal survey showed substantial temporal fluctuations,with individual waves of seroconversions and waning immunity. The high prevalencesobserved in bat communities, in most habitats and in species that do not share the samemicrohabitats and bioecological patterns, the temporal variations, and a rather short periodof detectable antibodies as observed in recaptured vampires suggest (i) frequent exposureof animals, (ii) an ability of the infected host to control and eliminate the virus, (iii) morerelaxed modes of exposure between bats than the commonly assumed infection via directcontact with saliva of infected animals, all of which should be further investigated.Conclusions / significanceWe hypothesize that RABV circulation in French Guiana is mainly maintained in the pristineforest habitats that may provide sufficient food resources to allow vampire bats, the mainprevalent species, to survive and RABV to be propagated. However, on the forest edge and in disturbed areas, human activities may induce more insidious effects such as defaunation.One of the ecological consequences is the disappearance of resources for tertiary or secondaryconsumers. Populations of vampires may then shift to alternative resources such ascattle, domestic animals and humans. Therefore, a good forest status, allowing both a dilutioneffect in highly rich bat communities and the maintenance of large populations ofmedium-sized and large mammals used as prey by vampires, should prevent their migrationto anthropized areas