Phylogeography of rabies virus isolated from herbivores and bats in the Espirito Santo State, Brazil
ABSTRACT Rabies is enzootic in the State of Espírito Santo, Brazil. Every year, cattle and horses die from rabies that is transmitted by the vampire bat Desmodus rotundus. This paper describes the spread of the rabies virus by the continuous diffusion model using relaxed random walks with BEAST software. Forty-one (41) sequences of gene G from the rabies virus that was isolated from bats and domestic herbivores from several areas of the state between 2006 and 2010 were analyzed. The phylogenetic tree showed three main clusters as well as two sub-clusters under cluster 2. A spatial analysis showed that three strains of the rabies virus spread independently. In general, central Espírito Santo, which is mountainous, was the area where separation of the virus strains occurred. This physical barrier, however, was overcome at some point in time, as samples from different lineages were found in the same microarea.
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ABSTRACT: Genetic lineages of dog-associated RABV still circulate in some areas of the North and Northeast of Brazil. In parallel, another RABV lineage circulates among wild canids in the Northeast, particularly the crab-eating fox (Cerdocyon thous). Although previous studies and phylogenetic analyses have been carried out, the way in which these lineages are dispersed temporally and spatially remained to be elucidated. In this study, RABV N gene sequences isolated from canids in North and Northeast Brazil were analyzed by the Bayesian Markov Chain Monte Carlo Method, and the results were then used in a phylogeographic study. It was inferred from the findings that the most recent common ancestor became established at the end of the nineteenth century on the border of the Brazilian states of Paraíba and Pernambuco and diversified into the lineages associated with dogs and C. thous. Around 1910, the original C. thous lineage diversified into two main sublineages in the same area, one of which migrated to the south and the other to the north. The dog-associated lineage diversified around 1945 and moved toward the north and south. From the phylogeographic analysis it was possible to infer not only the movement of the virus lineages but also the probable location where dispersion and diversification occurred. The methodology used here enabled the phylogeographic history of RABV in the region to be reconstructed, and the dispersion pattern of the virus can be used to predict its movements, making it easier to stop the advance of a rabies epidemic.Archives of Virology 06/2013; 158(11). DOI:10.1007/s00705-013-1755-y · 2.28 Impact Factor