Ecological factors associated with European bat lyssavirus seroprevalence in spanish bats.

Jordi Serra-Cobo,Marc López-Roig,Luisa Pilar Sánchez,Miquel Borrás,Magdalena Seguí,Jacint Nadal,Rachel Lavenir,Hervé Bourhy,Michelle L Baker

doi:10.1371/journal.pone.0064467

Abstract

Bats have been proposed as major reservoirs for diverse emerging infectious viral diseases, with rabies being the best known in Europe. However, studies exploring the ecological interaction between lyssaviruses and their natural hosts are scarce. This study completes our active surveillance work on Spanish bat colonies that began in 1992. Herein, we analyzed ecological factors that might affect the infection dynamics observed in those colonies. Between 2001 and 2011, we collected and tested 2,393 blood samples and 45 dead bats from 25 localities and 20 bat species. The results for dead confirmed the presence of EBLV-1 RNA in six species analyzed (for the first time in Myotis capaccinii). Samples positive for European bat lyssavirus-1 (EBLV-1)–neutralizing antibodies were detected in 68% of the localities sampled and in 13 bat species, seven of which were found for the first time (even in Myotis daubentonii, a species to date always linked to EBLV-2). EBLV-1 seroprevalence (20.7%) ranged between 11.1 and 40.2% among bat species and seasonal variation was observed, with significantly higher antibody prevalence in summer (July). EBLV-1 seroprevalence was significantly associated with colony size and species richness. Higher seroprevalence percentages were found in large multispecific colonies, suggesting that intra- and interspecific contacts are major risk factors for EBLV-1 transmission in bat colonies. Although bat-roosting behavior strongly determines EBLV-1 variability, we also found some evidence that bat phylogeny might be involved in bat-species seroprevalence. The results of this study highlight the importance of life history and roost ecology in understanding EBLV-1–prevalence patterns in bat colonies and also provide useful information for public health officials.

Highlights

High species diversity, worldwide distribution, high mobility and the fact that they represent a continuing source of emerging infections for humans make bats one of the most epidemiologically relevant groups of mammals to study disease ecology
Samples positive for European bat lyssavirus-1 (EBLV-1)–neutralizing antibodies were detected in 68% of the localities sampled and in 13 bat species, seven of which were found for the first time
EBLV-1–neutralizing antibodies were detected in 13 (65%) of the 20 species analyzed and showed broad variations among bat species (11.1–40.2%) (Table 1), representing the first time that EBLV-1–neutralizing antibodies were detected in P. pipistrellus, Pipistrellus kuhlii, Hypsugo savii, Myotis daubentonii, Myotis escalerai, Myotis capaccinii and Plecotus austriacus

Summary

Introduction

High species diversity (about 1,150 in the world), worldwide distribution, high mobility and the fact that they represent a continuing source of emerging infections for humans make bats one of the most epidemiologically relevant groups of mammals to study disease ecology. Numerous bat species have been found to be infected by lyssaviruses [3] and bats serve as the reservoirs of 10 of the 11 Lyssavirus species described, suggesting that the lyssaviruses originated in these mammals and progressively diverged from a common ancestor [4],[5]. Two new recently described tentative of the three novel Lyssavirus species further enlarged the genetic diversity of lyssaviruses found in bats [6,7,8]. EBLV-1 is widely distributed throughout Europe and two variants have distinct distributions and evolutionary histories: one is EBLV-1a, which has an east–west distribution from Russia to France, with very little genetic variation; and the other is EBLV-1b, which exhibits a south–north distribution and far more genetic diversity [9]

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