Molecular Epidemiological Analysis of Bat Rabies Viruses in Brazil

Abstract

ABSTRACT. A molecular epidemiological analysis was performed in 19 rabies viruses (RVs) isolated from haematophagous, frugivorous and insectivorous bats, in Sao Paulo, Brazil. The authors carried out RT-PCR for amplification of the RV nucleoprotein (N) gene, and determined 1,335 nucleotide sequences of N gene by direct sequencing method. Phylogenetic analysis, which was based on the N gene of Brazilian RV isolates identified presently and previously, revealed that RVs isolated from bats were genetically divided into four lineages had a tendency to depend on the host bat species. Rabies viruses (RVs) isolated in Brazil belong to genotype 1 of genus lyssavirus, family Rhabdoviridae. Ito et al. [7,8] reported that main reservoirs of RVs were dogs and vampire bats and that the RVs were classified into dogrelated RVs and vampire bat-related RVs in Brazil. In some areas of Brazil, the rabies outbreaks by both dog-and batrelated RVs occurred at the same time [7]. RVs have been isolated from not only haematophagous bats but also frugivorous and insectivorous bats in Brazil. In Argentina, RVs isolated from frugivorous bats (Artibeus lituratus) were identified to be the variant of RV associated with haematophagous bats by use of the monoclonal antibody panels [4]. Recently we have demonstrated that RVs isolated from Brazilian frugivorous bats (Artibeus spp.) were phylogenetically characterized as the vampire bat-related RV [18].There are many reports of human cases on infection with insectivorous bat RVs, and the number of the cases tend to increase in North America [10][11][12]. In 2002, Favi et al. [5] reported that insectivorous bat (Tadarida brasiliensis) RV variant was isolated from a human patient in Chile. In Colombia and Venezuela insectivorous bat RV variants were also isolated from dogs and cats, which were main RVtransmitters to human [2,14]. Although some kinds of insectivorous bats have been diagnosed as RV-positive in Brazil, there have been no reports of the human case on infection with insectivorous bat RV variants until now. RVpositive insectivorous bats were, however, found in urban areas, and this fact has been considered as important problems in public health [1,6,17,21].As there is little information about the genetic characteristics of bat-related RVs in Brazil, authors determined nucleotide sequences on the N gene of RVs isolated from 9 Brazilian bat species. Phylogenetic analysis was also performed for the epidemiological study with the isolates identified previously. MATERIALS AND METHODS Viruses:In this study, 19 RVs were isolated from 3 haematophagous bats (Desmodus rotundus), 1 frugivorous bat (Artibeus lituratus), 13 insectivorous bats (3 Nyctinomops laticaudatus, 2 Eumops auripendulus, 4 Eptesicus furinalis, 2 Molossus molossus, 1 Molossus abrasus and 1 Molossus rufus) and 2 unclassified bats, and their nucleoprotein gene sequences were determined. Brain materials from these bats were diagnosed as RV-positive by immunofluorescent antibody test (FAT) using a rabbit polyclonal anti-rabies nucle...

Monoclonal antibodies for characterization of rabies virus isolated from non-hematophagous bats in Brazil

“…All isolates confirmed as antigenic variants belong to the species Rabies virus of the genus Lyssavirus, like all the other isolates on the American continents and Caribbean [23,24].…”

Genetic Analysis of Phosphoprotein and Matrix Protein of Rabies Viruses Isolated in Brazil

“…Phylogenetic analyses based on the P and M genes revealed the existence of several Brazilian RV variants corresponding to phylogenetic analyses targeting the viral N and G genes [19,25,26,41,42,44,45]. Phylogenetic analysis showed two clusters consisting of chiroptera-or carnivora-related RV isolates.…”

“…sp.) have frequently been typed as vampire bat-related RVs in Brazil [19,25,26,41,42,44,45]. Variability has also been reported in the G protein, a major contributor to the pathogenicity of the virus, in which several amino acid substitutions at antigenic sites associated with the pathogenicity and immunogenicity of the virus have been identified in Brazilian RV variants [41].…”

Filogenia de vírus da raiva isolados de morcegos frugívoros do gênero Artibeus e relacionados a morcegos hematófagos com base nos genes codificadores da nucleoproteína N e glicoproteína G

“…A heterogeneidade de isolados de RABV expressa genealogicamente sob a forma de grupos específicos a certos tipos de mamíferos é um episódio detectado entre distintos hospedeiros (DIAZ et al, 1994;DE MATTOS et al, 1996ITO et al, 2001;FAVORETTO et al, 2002;KOBAYASHI et al, 2005KOBAYASHI et al, , 2007CARNIELI JR. et al, 2008).…”