The genetic lineage of rabies virus (RABV) associated with dogs has not been found in the state of São Paulo since 1998, and all cases of rabies in domestic animals reported since then have involved ...the RABV lineage that circulates in bats. As there has been a change in the rabies transmission cycle in cats and dogs, we decided to analyze the tests used to diagnose rabies in these animals in the 15-year period from 2002 to 2016 in the state of São Paulo. During this period, 85,508 central nervous system (CNS) samples from dogs and cats were submitted to the Rabies Diagnosis Section at the Pasteur Institute of São Paulo for testing. All of the samples were tested by the fluorescent antibody test (FAT) and at least one of the following three tests: mouse inoculation test (MIT), rabies tissue culture infection test (RTCIT) and reverse transcription polymerase chain reaction (RT-PCR). Of all the samples tested, twenty were positive in at least one of these assays. Four other positive samples were identified at other institutions in the state of São Paulo. Of the twenty samples that tested positive at the Pasteur Institute of São Paulo, nine were tested by FAT, and the results were subsequently confirmed by other techniques; five gave inconclusive results, and therefore, other techniques had to be used as soon as possible in case the samples were positive; and six were negative by FAT and positive by one or more of the following tests: RTCIT, MIT and RT-PCR. Genetic typing of isolates from eighteen samples identified them as the lineage circulating in bats. In light of this finding, which indicates that genetic lineages associated with bats are circulating in domestic animals in the state of São Paulo, when the results of FAT carried out with samples from aggressive cats and dogs are inconclusive, complementary tests should be used. Decomposing samples and samples for which FAT was inconclusive should be tested using molecular techniques so that a definitive result can be obtained quickly and timely post-exposure prophylaxis can be administered to exposed individuals.
Cases of canine rabies continue to occur in North and Northeast Brazil, and the number of notifications of rabies cases in wild canids has increased as a result of the expansion of urban areas at the ...expense of areas with native vegetation. In light of this, we performed molecular characterization of rabies virus isolates from dogs and
Cerdocyon thous
from various states in North and Northeast Brazil. In all, 102 samples from dogs (n = 56) and
Cerdocyon thous
(n = 46) collected between 2006 and 2012 were used. The nucleotide sequences obtained for the N gene of rabies virus were analyzed, and phylogenetic analysis revealed the presence of two distinct genetic lineages, one associated with canids and one with bats, and, within the canid cluster, two distinct sublineages circulating among dogs and
Cerdocyon thous
. In addition, phylogenetic groups associated with geographic region and fourteen cases of interspecific infection were observed among the isolates from canids. Our findings show that analysis of rabies virus lineages isolated from reservoirs such as canids must be constantly evaluated because the mutation rate is high.
The rabies cases in dogs and wild canids in Northeastern Brazil are a public and animal health problem. This paper describes the identities of the coding region of the N-gene of Rabies virus (RABV) ...isolated in canids from Northeastern Brazil. The genetic tree generated using the sequence data described here divided the cluster BRAZILAN CANIDS into two subclusters (DOG-RELATED STRAINS and WILD CANID-RELATED STRAINS) with identities greater than those already described. The two subclusters are sub-divided into geographic groups related to the origin of the isolates, suggesting a long-standing ecological coexistence of the sequence types characteristic of the groups.
This article also analyzes the 513-nucleotide stretch of the mitochondrial DNA control region of rabies-positive canids from Northeastern Brazil with a view to identifying the main RABV host among them. Among the four species of wild canids found in the region, two (Cerdocyon thous and Pseudalopex vetulus) are frequently associated with rabies. Phylogenetic analysis of sequence data generated from mtDNA suggests that C. thous is the main wild canid host in the region. The results obtained in this study are in concordance with the zoology and ecology of wild canids, and thus, help improve epidemiologic vigilance of rabies and allow a more targeted control of the disease.
In Brazil, bats have been assigned an increasing importance in public health as they are important rabies reservoirs. Phylogenetic studies have shown that rabies virus (RABV) strains from frugivorous ...bats Artibeus spp. are closely associated to those from the vampire bat Desmodus rotundus, but little is known about the molecular diversity of RABV in Artibeus spp. The N and G genes of RABV isolated from Artibeus spp. and cattle infected by D. rotundus were sequenced, and phylogenetic trees were constructed. The N gene nucleotides tree showed three clusters: one for D. rotundus and two for Artibeus spp. Regarding putative N amino acid-trees, two clusters were formed, one for D. rotundus and another for Artibeus spp. RABV G gene phylogeny supported the distinction between D. rotundus and Artibeus spp. strains. These results show the intricate host relationship of RABV's evolutionary history, and are invaluable for the determination of RABV infection sources.
Thirty-eight samples of Rabies Virus isolated from dogs and crab-eating foxes (
Cerdocyon thous) in Northeastern Brazil were characterized genetically by analyzing the G gene and the psi region. The ...results show that there are two groups of Rabies Virus lineages circulating among domestic and wild animals in the region. The topologies of the phylogenetic trees of the G gene and psi region are similar and reveal the existence of geographic groups. The genetic diversity of the lineages isolated from wild animals (wild group) was approximately twice that of the lineages isolated from domestic animals (domestic group), and the genetic distance between the two groups was 9.93%. Polymorphism analysis revealed specific intra- and inter-group molecular signatures for both the G gene and psi region. Together with the analysis of the N gene undertaken previously, the results of this study confirm the existence of a Rabies Virus phylogroup in Northeastern Brazil (NB) circulating in the
C. thous population, making this species a rabies biotype in the region.
The biogeographical history of rabies can be reconstructed using molecular data. This work describes the genetic characterization of the
Rabies virus variant that circulates in the
Desmodus rotundus ...(vampire bat) population in an epizootic area and is transmitted to herbivorous livestock. The N and G genes of this virus were sequenced, and the phylogenetic trees generated were topologically concordant. Three genetic clusters were identified in the epizootic area and were designated RD1, RD2 and RD3. The results show that the origins of the epizootics in areas RD1 and RD2 were different and that the epizootic in area RD3 was the result of expansion of that in area RD2. The two genes analyzed are conserved, and their identities, which are greater than 98%, were maintained over time and space. The genetic sequences in this study were compared with others retrieved from GenBank, and the high identity of the N and G genes was also shown to be maintained over time and space. The results suggest that the
D. rotundus lineages of the
Rabies virus from the Atlantic coast of South America are highly conserved.
The purpose of this study was to characterize astrovirus in faecal samples collected from children with and without diarrhea in São Paulo, Brazil, grouped into two sets: EPM and HU. Detection and ...genotyping were carried out using reverse transcription nested polymerase chain reaction (RT-PCR) with specific primers directed towards the genome open reading frame 2 (ORF2). Results for EPM set showed that 66/234 (28.2%) were positive: 28/94 (29.7%) from children with acute diarrhea, 14/45 (31.1%) with persistent diarrhea, and 9/55 (16.3%) from control individuals. No data was available for 15/40 (37.5%) of samples. Mixed infections with other viruses were found in 33 samples. In the HU, 18/187 (9.6%) were positive: 12/158 (7.6%) from individuals with acute diarrhea and 6/29 (20.7%) from control children. Four samples were mixed with other viruses. Out of 66 astrovirus positive EPM samples, 18 (27.2%) were characterized as human astrovirus type-1 (HAstV-1), two (3.0%) as HAstV-2, two (3.0%) as HAstV-3, and three (4.5%) as HAstV-8. Among 18 astrovirus positive HU samples, one (5.5%) was characterized as HAstV-1, six (33.3%) as HAstV-2, and one (5.5%) as HAstV-8. Two HAstV-8 genotyped samples were further confirmed by nucleotide sequencing. Our results shows that astroviruses are circulating in a constant manner in the population, with multiple serotypes, in higher frequency than it was described for other Brazilian regions. For the first time in Sao Paulo, Brazil, it was shown that astroviruses play an important role in children gastroenteritis, as described for most locations where they were detected.
This article reports on the identification of a group 2 coronavirus (BatCoV DR/2007) in a Desmodus rotundus vampire bat in Brazil. Phylogenetic analysis of ORF1b revealed that BatCoV DR/2007 ...originates from a unique lineage in the archetypical group 2 coronaviruses, as described for bat species elsewhere with putative importance in Public Health.
The Ministry of Health's National Human Rabies Control Program advocates pre-exposure prophylaxis (PEP) for professionals involved with animals that are at risk of contracting rabies. We report an ...antemortem and postmortem diagnosis of rabies in a veterinarian who became infected when handling herbivores with rabies. The antemortem diagnosis was carried out with a saliva sample and a biopsy of hair follicles using molecular biology techniques, while the postmortem diagnosis used a brain sample and conventional techniques. The veterinarian had collected samples to diagnose rabies in suspect herbivores (bovines and caprines) that were subsequently confirmed to be positive in laboratory tests. After onset of classic rabies symptoms, saliva and hair follicles were collected and used for antemortem diagnostic tests and found to be positive by RT-PCR. Genetic sequencing showed that the infection was caused by variant 3 (Desmodus rotundus), a finding confirmed by tests on the brain sample. It is essential that professionals who are at risk of infection by the rabies virus undergo pre-exposure prophylaxis. This study also confirms that molecular biology techniques were used successfully for antemortem diagnosis and therefore not only allow therapeutic methods to be developed, but also enable the source of infection in human rabies cases to be identified accurately and quickly.
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