Molecular epidemiological tracing of a cattle rabies outbreak lasting less than a month in Rio Grande do Sul in southern Brazil.

Takuya Itou,Adolorata A B Carvalho,Eduardo R Deberaldini,Takeo Sakai,Yuki Kobayashi,Nobuyuki Mochizuki,Fumio H Ito,Toshiharu Fukayama

doi:10.1186/s13104-016-1898-5

Takuya Itou, Adolorata A B Carvalho + Show 6 more

Open Access

https://doi.org/10.1186/s13104-016-1898-5

Copy DOI

Abstract

BackgroundVampire bat-transmitted cattle rabies cases are typically encountered in areas where the disease is endemic. However, over the period of a month in 2009, an outbreak of cattle rabies occurred and then ended spontaneously in a small area of the Rio Grande do Sul State in southern Brazil. To investigate the epidemiological characteristics of this rabies outbreak in Rio Grande do Sul, 26 nucleotide sequences of rabies virus (RABV) genomes that were collected in this area were analyzed phylogenetically.ResultsNucleotide sequence identities of the nucleoprotein gene and G–L intergenic region of the 26 RABVs were greater than 99.6 %. Phylogenetic analysis showed that all RABVs clustered with the vampire bat-related cattle RABV strains and that the RABVs were mainly distributed in southern Brazil.ConclusionsThe findings of the present study suggested that a small population of rabid vampire bats carrying a single RABV strain produced a spatiotemporally restricted outbreak of cattle rabies in southern Brazil.Electronic supplementary materialThe online version of this article (doi:10.1186/s13104-016-1898-5) contains supplementary material, which is available to authorized users.

Highlights

Vampire bat-transmitted cattle rabies cases are typically encountered in areas where the disease is endemic
The genetic analysis revealed that the nucleotide and amino acid sequences were almost identical among the 26 rabies virus (RABV) and shared a common ancestor, suggesting the RABV strain was transmitted from a small population of rabid vampire bats infected with RABV, which may be derived from a single introduction, to a cattle population grazing in Nova Roma do Sul
We were unable to investigate the prevalence of rabid vampire bats in this area, the findings of the present study revealed that the 26 RABVs correspond with the “Old strains” lineage

Summary

Introduction

Vampire bat-transmitted cattle rabies cases are typically encountered in areas where the disease is endemic. Over the period of a month in 2009, an outbreak of cattle rabies occurred and ended spontaneously in a small area of the Rio Grande do Sul State in southern Brazil. To investigate the epidemiological characteristics of this rabies outbreak in Rio Grande do Sul, 26 nucleotide sequences of rabies virus (RABV) genomes that were collected in this area were analyzed phylogenetically. Genetic diversity among rabies viruses (RABVs) depends on the host species and its geographic distribution. Rabies is endemic in Brazil, and RABVs have been isolated from a variety of mammalian hosts, including dogs, foxes, cats, cattle, and hematophagous, insectivorous and frugivorous bats [1,2,3]. Vampire bat-related rabies is a serious problem from both animal and public health standpoints

Methods

Results

Discussion

Conclusion