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1.
The complete genome sequences of two Brazilian wild-type rabies viruses (RABV), a BR-DR1 isolate from a haematophagous bat (Desmodus rotundus) and a BR-AL1 isolate from a frugivorous bat (Artibeus lituratus), were determined. The genomes of the BR-DR1 and BR-AL1 had 11,923 and 11,922 nt, respectively, and both encoded the five standard genes of rhabdoviruses. The complete nucleotide sequence identity between the BR-DR1 and BR-AL1 isolates was 97%. The BR-DR1 and BR-AL1 isolates had some conserved functional sites revealed by the fixed isolates, whereas both isolates had unique amino acid substitutions in the antigenic region IV of the nucleocapsid gene. Therefore, it is speculated that both isolates were nearly identical in virologic character. According to our phylogenetic analysis based on the complete genomes, both isolates belonged to genotype 1, and to the previously defined "vampire bat-related RABV lineage" which consisted of mainly D. rotundus- and A. lituratus-isolates; however, a branch pattern with high bootstrap values suggested that BR-DR1 was more closely related to the 9001FRA isolate, which was collected from a dog bitten by a bat in French Guiana, than to BR-AL1. This result suggests that the vampire bat-related RABV lineage includes Brazilian vampire bat and Brazilian frugivorous bat RABV and is further divided into Brazilian vampire bat and Brazilian frugivorous bat RABV sub-lineages. The phylogenetic analysis based on the complete genomes was valuable in discriminating among very closely related isolates.  相似文献   

2.
Molecular epidemiological analysis of bat rabies viruses in Brazil   总被引：9，自引：0，他引：9  
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. The first lineage consisted mainly of haematophagous bat (Desmodus rotundus) isolates, including frugivorous bat (Artibeus spp.) isolates. Other three lineages consisted of insectivorous bat isolates; mainly Eptesicus spp., Molossus spp. and Nyctinomops spp. isolates, respectively. These results indicate a possibility of that there are bat species-specific RV variants in Brazil.  相似文献   

3.
Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n = 35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n = 3), stomach (n = 1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRT-PCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild.  相似文献   

4.
The rabies viruses of bats   总被引：5，自引：0，他引：5  
In the 1930s rabies was shown to affect blood-, insect- and fruit-eating bats. We have prepared anti-nucleocapsid monoclonal antibodies (MAbs) using Mokola and bat (Lagos, Duvenhage and Denmark) rabies viruses as immunogens. With these MAbs we have examined rabies viruses from vampire, insectivorous and frugivorous bats from the Americas, Africa, Europe and the Soviet Union and have compared them with isolates from terrestrial species including man. As well as confirming the findings of others with viruses of African and American bat origin, the results revealed the presence of a second biotype in European bats and demonstrated the presence of serotype 1 as well as serotype 4 viruses in bats of the Soviet Union.  相似文献   

5.
Geographical distribution of vampire bat-related cattle rabies in Brazil   总被引：6，自引：0，他引：6  
Seventy-seven rabies virus (RV) isolates originating from Brazilian cattle were genetically characterized. Partial nucleoprotein gene sequences of these isolates were phylogenetically and geographically analyzed. Cattle isolates, which clustered with the vampire bat-related RV group, were further subdivided into nine genetic subgroups. These subgroups were distributed widely in lowland regions, with some subgroups separated from each other by mountain ranges. In addition, separation of the groups in mountainous regions was correlated with altitude. These results indicate that cattle rabies is derived from several regionally-defined variants, which suggests that its geographical distribution is related to that of the vampire bat population.  相似文献   

6.
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7.
Bats represent the largest dietary radiation in a single mammalian order, and have become an emerging model group for studying dietary evolution. Taste receptor genes have proven to be molecular signatures of dietary diversification in bats. For example, all 3 extant species of vampire bats have lost many bitter taste receptor genes (Tas2rs) in association with their dietary shift from insectivory to sanguivory. Indeed, only 8 full-length Tas2rs were identified from the high-quality genome of the common vampire bat (Desmodus rotundus). However, it is presently unknown whether these bitter receptors are functional, since the sense of taste is less important in vampire bats, which have an extremely narrow diet and rely on other senses for acquiring food. Here, we applied a molecular evolutionary analysis of Tas2rs in the common vampire bat compared with non-vampire bats. Furthermore, we provided the first attempt to deorphanize all bitter receptors of the vampire bat using a cell-based assay. We found that all Tas2r genes in the vampire bat have a level of selective pressure similar to that in non-vampire bats, suggesting that this species must have retained some bitter taste functions. We demonstrated that 5 of the 8 bitter receptors in the vampire bat can be activated by some bitter compounds, and observed that the vampire bat generally can not detect naturally occurring bitter compounds examined in this study. Our study demonstrates functional retention of bitter taste in vampire bats as suggested by cell-based functional assays, calling for an in-depth study of extra-oral functions of bitter taste receptors.  相似文献   

8.
To investigate the genetic characteristics of phosphoprotein (P) and matrix protein (M) genes of variable rabies virus (RV) prevalent in Brazil, the authors genetically characterized the P and M genes from 30 Brazilian RV field isolates. Phylogenetic analysis based on the P and M genes revealed the presence of six RV variants that consisted primarily of three insectivorous bats, the vampire bat, dog and fox in Brazil. Specific amino acid substitutions corresponding to these phylogenetic lineages were observed, with Asp(42) and Glu(62) in the P protein found to be characteristic of Brazilian chiroptera- and carnivora-related RVs, respectively. Amino acid sequence motifs predicted to associate with a viral function in the P and M proteins were conserved among Brazilian RV variants.  相似文献   

9.
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10.
During 2010, 48 states and Puerto Rico reported 6,154 rabid animals and 2 human rabies cases to the CDC, representing an 8% decrease from the 6,690 rabid animals and 4 human cases reported in 2009. Hawaii and Mississippi did not report any laboratory-confirmed rabid animals during 2010. Approximately 92% of reported rabid animals were wildlife. Relative contributions by the major animal groups were as follows: 2,246 raccoons (36.5%), 1,448 skunks (23.5%), 1,430 bats (23.2%), 429 foxes (6.9%), 303 cats (4.9%), 71 cattle (1.1 %), and 69 dogs (1.1 %). Compared with 2009, number of reported rabid animals decreased across all animal types with the exception of a 1 % increase in the number of reported rabid cats. Two cases of rabies involving humans were reported from Louisiana and Wisconsin in 2010. Louisiana reported an imported human rabies case involving a 19-year-old male migrant farm worker who had a history of a vampire bat (Desmodus rotundus) bite received while in Mexico. This represents the first human rabies case reported in the United States confirmed to have been caused by a vampire bat rabies virus variant. Wisconsin reported a human rabies case involving a 70-year-old male that was confirmed to have been caused by a rabies virus variant associated with tri-colored bats (Perimyotis subflavus).  相似文献   

11.
Genetic and phylogenetic analyses of the region containing the glycoprotein (G) gene, which is related to pathogenicity and antigenicity, and the G-L intergenic region were carried out in 14 Brazilian rabies virus isolates. The isolates were classified as dog-related rabies virus (DRRV) or vampire bat-related rabies virus (VRRV), by nucleoprotein (N) analysis. The nucleotide and amino acid (AA) homologies of the area containing the G protein gene and G-L intergenic region were generally lower than those of the ectodomain. In both regions, nucleotide and deduced AA homologies were lower among VRRVs than among DRRVs. There were AA differences between DRRV and VRRV at 3 antigenic sites and epitopes (IIa, WB+ and III), suggesting that DRRV and VRRV can be distinguished by differences of antigenicity. In a comparison of phylogenetic trees between the ectodomain and the area containing the G protein gene and G-L intergenic region, the branching patterns of the chiropteran and carnivoran rabies virus groups differed, whereas there were clear similarities in patterns within the DRRV and VRRV groups. Additionally, the VRRV isolates were more closely related to chiropteran strains isolated from Latin America than to Brazilian DRRV. These results indicate that Brazilian rabies virus isolates can be classified as DRRV or VRRV by analysis of the G gene and the G-L intergenic region, as well as by N gene analysis.  相似文献   

12.
Haematophagous bats exist only in Latin America, from México to the Northern provinces of Argentina. They are represented by three species, Desmodus rotundus, Diphylla ecaudata and Diaemus youngii. While two species feed only on blood of wild birds, one species, D. rotundus, causes losses feeding on livestock and could be a vector for rabies virus. The cases in which humans were bitten by the bat have increased in Brazil. Bats became a target of control activities by farming communities and local governments. Indiscriminate actions such as poisoning bats and destroying their roosts put the lives of other bat species, which are extremely important for the ecologic balance, at risk. The vaccination of exposed livestock against rabies, which would protect the endangered livestock, is not regularly carried out. The importance and current status of D. rotundus in the transmission of rabies in Brazil, the Public Health aspects, the importance for the livestock industry are shown and the consequences of reducing bat population are discussed. Alternatives to an indiscriminate bat-population reduction in the control of rabies are proposed.  相似文献   

13.
The intensification of dog, cat and livestock vaccination campaigns significantly reduced rabies cases in humans and domestic animals in Ceará State, Brazil. However, sylvatic animals—bats (order Chiroptera), wild canids, raccoons and non‐human primates— remain as reservoirs for the virus. Our hypothesis is that surveillance and monitoring of rabies virus in bats, especially passive surveillance, is of fundamental importance, besides the implementation of health education and strengthening of surveillance actions in humans exposed to aggressions. Thus, we assessed the occurrence of rabies virus in animals focusing on bats, before and after launching of the Sylvatic Rabies Surveillance Program in 2010. Surveillance data from the 184 municipalities of Ceará State were analysed, collected during the periods 2003–2010 (active surveillance) and 2011–2016 (passive surveillance), respectively. A total of 13,543 mammalian samples were received for rabies diagnosis from 2003 to 2016. Of these, 10,960 were from dogs or cats (80.9%), 1,180 from bats (8.7%), 806 from other sylvatic animals (foxes, marmosets, raccoons; 6.0%) and 597 from herbivores (cattle, goats, sheep, equines, pigs; 4.4%). A total of 588 (4.3%) samples were positive for rabies. About 8.4% (99/1,180) of the bat samples were infected with rabies virus, 92 (92.9%) of these were from non‐haematophagous bat species and 7 (7.1%) from haematophagous species. The number of bat samples received and infection rates increased considerably, after a shift from active surveillance (9/355 [2.5%] samples positive), to passive surveillance (90/825 [10.9%] samples positive). Surveillance of rabies virus in bats is fundamental for human and domestic animal health in Ceará State. Bats have to be considered as targets in surveillance and control programmes. Virus lineages should be characterized to increase knowledge on transmission dynamics of sylvatic rabies virus to domestic animals and the human population, and to provide additional evidence for planning and implementation of improved control measures.  相似文献   

14.
Guaraqueçaba city is a rain forest environmental protected area located on the southern coast of Brazil. Recently, the local Animal Health Service has noticed haematophagous bats feeding from humans and domestic animals, as well as bat colonies located in houses and public schools. In 2007, two non‐haematophagous bats were tested positive by direct immunofluorescence for rabies in a nearby city. Native fauna and environmental laws protect non‐haematophagous bats in Brazilian preserved areas such as Guaraqueçaba, making non‐haematophagous bat population control almost impossible. Accordingly, the aim of this study was to evaluate a simple and feasible educational protocol applied by a multi‐institutional task force in local elementary schools to prevent rabies transmitted by bats. Information was transmitted to children by video, lectures and oral question–answer section; evaluation was made by written questionnaires to teachers and students. Interinstitutional task force included public and animal health public services, a federal university and the city secretary of environment, of education, of agriculture and of animal health, and also participation of local community. Information was effectively absorbed by children when evaluated just after being given. As important, questionnaires showed that handling and playing with bats at day time was common in several elementary school students, exposing themselves to what may represent higher risk of rabies transmission than haematophagous bat feeding directly from humans. Training of teachers and students may effectively prevent rabies by bats in such communities. Insertion of this subject into science content of local elementary school educational programme was proposed in order to establish a continuing education programme on rabies transmitted by bats in environmental preserved areas.  相似文献   

15.
In Europe bat rabies in Daubenton's bats (Myotisdaubentonii) and in Pond bats (Myotis dasycneme) caused by the European bat lyssavirus 2 (EBLV-2) has been confirmed in less than 20 cases to date. Here we report the second encounter of this virus species in Germany. A Daubenton's bat found grounded in the zoological garden in Magdeburg died shortly after. In the frame of a retrospective study the bat carcass was eventually transferred to the national reference laboratory for rabies at the Friedrich-Loeffler-Institute for rabies diagnosis. Lyssavirus was isolated and characterized as EBLV-2.  相似文献   

16.
Rabies is caused by infection with a lyssavirus. Bat rabies is of concern for both public health and bat conservation. The current method for lyssavirus prevalence studies in bat populations is by oral swabbing, which is invasive for the bats, dangerous for handlers, time‐consuming and expensive. In many situations, such sampling is not feasible, and hence, our understanding of epidemiology of bat rabies is limited. Faeces are usually easy to collect from bat colonies without disturbing the bats and thus could be a practical and feasible material for lyssavirus prevalence studies. To further explore this idea, we performed virological analysis on faecal pellets and oral swabs of seven serotine bats (Eptesicus serotinus) that were positive for European bat 1 lyssavirus in the brain. We also performed immunohistochemical and virological analyses on digestive tract samples of these bats to determine potential sources of lyssavirus in the faeces. We found that lyssavirus detection by RT‐qPCR was nearly as sensitive in faecal pellets (6/7 bats positive, 86%) as in oral swabs (7/7 bats positive, 100%). The likely source of lyssavirus in the faeces was virus excreted into the oral cavity from the salivary glands (5/6 bats positive by immunohistochemistry and RT‐qPCR) or tongue (3/4 bats positive by immunohistochemistry) and swallowed with saliva. Virus could not be isolated from any of the seven faecal pellets, suggesting the lyssavirus detected in faeces is not infectious. Lyssavirus detection in the majority of faecal pellets of infected bats shows that this novel material should be further explored for lyssavirus prevalence studies in bats.  相似文献   

17.
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18.
Characteristics of bat rabies in Alberta.   总被引：4，自引：0，他引：4       下载免费PDF全文
Rabies in bats was monitored in Alberta from 1971 to 1978 Big brown bats replaced silver-haired bats as the species most frequently reported rabid during these years. Rabies infection was comparatively high among little brown bats in central Alberta in 1973 and has subsequently declined. Only one rabid little brown bat was discovered in southern Alberta which is populated by a different subspecies. Outbreaks of rabies in little brown and big brown bat colonies tended to be brief events. Observations of free-ranging bats with probable furious rabies suggested that bats do not generally identify humans as targets for attack. Independent trends in infection rates suggested that spread of rabies is primarily intraspecific but there is evidence that migratory bats play a role in introduction and maintenance of rabies in northern temperate bat communities. The dynamics of bat rabies in Alberta are discussed.  相似文献   

19.
Bats are hosts of diverse coronaviruses (CoVs) known to potentially cross the host–species barrier. For analysing coronavirus diversity in a bat species‐rich country, a total of 421 anal swabs/faecal samples from Costa Rican bats were screened for CoV RNA‐dependent RNA polymerase (RdRp) gene sequences by a pancoronavirus PCR. Six families, 24 genera and 41 species of bats were analysed. The detection rate for CoV was 1%. Individuals (n = 4) from four different species of frugivorous (Artibeus jamaicensis, Carollia perspicillata and Carollia castanea) and nectivorous (Glossophaga soricina) bats were positive for coronavirus‐derived nucleic acids. Analysis of 440 nt. RdRp sequences allocated all Costa Rican bat CoVs to the α‐CoV group. Several CoVs sequences clustered near previously described CoVs from the same species of bat, but were phylogenetically distant from the human CoV sequences identified to date, suggesting no recent spillover events. The Glossophaga soricina CoV sequence is sufficiently dissimilar (26% homology to the closest known bat CoVs) to represent a unique coronavirus not clustering near other CoVs found in the same bat species so far, implying an even higher CoV diversity than previously suspected.  相似文献   

20.
Veterinary surgeons in Australia must be aware of the emerging viral diseases and their potential effects on public health generally and, more specifically, on the veterinary profession. Australian bat lyssavirus was identified in 1996 and causes rabies-like disease in bats and humans. Two humans from Queensland have died of Australian bat lyssavirus encephalitis. Surveillance has shown that all Australian bats must be considered carriers of this new virus, therefore protective apparel should be used when handling bats. The pre-exposure regimen of inactivated rabies vaccine (Pasteur Mérieux) provides protection against infection. As part of the preventive regimen, at risk groups, such as veterinary surgeons, should seriously consider pre-exposure rabies vaccination. The post-exposure protocol involves administration of human rabies immunoglobulins and five intramuscular injections of the inactivated rabies vaccine.  相似文献   

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