RESUMO
Bats are the second most diverse order of mammals and play a central role in ecosystem dynamics. They are also important reservoirs of potentially zoonotic microorganisms, of which rabies virus is the most lethal among the bat-transmitted zoonotic pathogens. Importantly, recent outbreaks of human rabies have been reported from the Brazilian Amazon. Here we present a survey of bat species and rabies virus (RABV) circulation in a bat assemblage in the Marajó region, northern Brazil. Using data from mist-net captures and bioacoustic sampling, 56 bat species were recorded along the Jacundá River basin over a 10-day expedition in November 2022. For the investigation of RABV, we used the direct fluorescent antibody test (DFAT) and the rapid fluorescent focus inhibition test (RFFIT). In total, 159 bat individuals from 22 species were investigated for RABV. Five adults of the common vampire bat, Desmodus rotundus, showed RABV-specific antibodies in serum samples. Additionally, we report on local residents with injuries caused by D. rotundus bites and the occurrence of colonies of non-hematophagous bats from different species roosting inside human residences. This scenario raises concerns about the risks of new cases of human rabies and other zoonotic diseases associated with bats in the region and highlights the need for epidemiological surveillance and mitigation measures to prevent outbreaks of emerging infectious diseases.
Assuntos
Anticorpos Antivirais , Quirópteros , Surtos de Doenças , Vírus da Raiva , Raiva , Zoonoses , Quirópteros/virologia , Animais , Brasil/epidemiologia , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/classificação , Raiva/epidemiologia , Raiva/veterinária , Raiva/virologia , Humanos , Zoonoses/epidemiologia , Zoonoses/virologia , Anticorpos Antivirais/sangue , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , AdolescenteRESUMO
Rabies, a fatal zoonotic viral disease affecting mammals, including humans, remains a significant global health concern, particularly in low-income countries. The disease, primarily transmitted through infected animal saliva, prompts urgent diagnosis for timely post-exposure prophylaxis (PEP). The gold standard diagnostic test, direct fluorescent antibody test (dFAT), while sensitive, suffers from limitations such as subjective interpretation and high costs. As a confirmatory technique, the LN34 Pan-Lyssavirus RT-qPCR assay has emerged as a promising tool for universal Lyssavirus detection. This study evaluated its performance using 130 rabies virus isolates representing eleven Brazilian variants and 303 clinical samples from surveillance operations. The LN34 assay demonstrated 100% sensitivity and 98% specificity compared to dFAT. Additionally, it detected all samples, including those missed by dFAT, indicating superior sensitivity. The assay's specificity was confirmed through Sanger nucleotide sequencing, with only a minimal false-positive rate. Comparative analysis revealed higher accuracy and concordance with dFAT than traditional rabies tissue culture infection tests (RTCIT). False-negative RTCIT results were attributed to low viral load or suboptimal sampling. These findings underscore the LN34 assay's utility as a confirmatory technique, enhancing rabies surveillance and control in Brazil. Its widespread adoption could significantly improve diagnostic sensitivity, crucial for effective PEP and public health interventions.
Assuntos
Vírus da Raiva , Raiva , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Raiva/diagnóstico , Raiva/veterinária , Raiva/virologia , Brasil , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/classificação , Humanos , Animais , Reação em Cadeia da Polimerase em Tempo Real/métodos , Lyssavirus/genética , Lyssavirus/isolamento & purificação , Lyssavirus/classificação , RNA Viral/genética , Carga ViralRESUMO
The rabies virus (RABV) is characterized by a history dominated by host shifts within and among bats and carnivores. One of the main outcomes of long-term RABV maintenance in dogs was the establishment of variants in a wide variety of mesocarnivores. In this study, we present the most comprehensive phylogenetic and phylogeographic analysis, contributing to a better understanding of the origins, diversification, and the role of different host species in the evolution and diffusion of a dog-related variant endemic of South America. A total of 237 complete Nucleoprotein gene sequences were studied, corresponding to wild and domestic species, performing selection analyses, ancestral states reconstructions, and recombination analyses. This variant originated in Brazil and disseminated through Argentina and Paraguay, where a previously unknown lineage was found. A single host shift was identified in the phylogeny, from dog to the crab-eating fox (Cerdocyon thous) in the Northeast of Brazil. Although this process occurred in a background of purifying selection, there is evidence of adaptive evolution -or selection of sub-consensus sequences- in internal branches after the host shift. The interaction of domestic and wild cycles persisted after host switching, as revealed by spillover and putative recombination events.
Assuntos
Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Animais , Animais Domésticos/virologia , Animais Selvagens/virologia , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Evolução Molecular , Raposas/virologia , Nucleoproteínas/genética , Filogenia , Raiva/epidemiologia , Raiva/virologia , Vírus da Raiva/classificação , Recombinação Genética , América do Sul/epidemiologiaRESUMO
Mongooses, a nonnative species, are a known reservoir of rabies virus in the Caribbean region. A cross-sectional study of mongooses at 41 field sites on the US Virgin Islands of St. Croix, St. John, and St. Thomas captured 312 mongooses (32% capture rate). We determined the absence of rabies virus by antigen testing and rabies virus exposure by antibody testing in mongoose populations on all three islands. USVI is the first Caribbean state to determine freedom-from-rabies for its mongoose populations with a scientifically-led robust cross-sectional study. Ongoing surveillance activities will determine if other domestic and wildlife populations in USVI are rabies-free.
Assuntos
Animais Selvagens/virologia , Reservatórios de Doenças/virologia , Herpestidae/virologia , Vírus da Raiva/isolamento & purificação , Animais , Estudos Transversais , Vírus da Raiva/classificação , Vírus da Raiva/genética , Ilhas Virgens AmericanasRESUMO
Objetivo: Descrever os casos de raiva humana no estado do Ceará, Brasil, no período 1970-2019. Métodos: Estudo descritivo, sobre dados secundários da Secretaria da Saúde e do hospital de referência do Ceará. Resultados: Dos 171 casos, 75,7% ocorreram em homens, 60,0% nas idades até 19 anos e 56,0% em áreas urbanas. O cão foi agente transmissor em 74,0% dos casos; sagui em, 16,7%; e morcego, em 7,3%. Entre 1970 e 1978, houve crescimento do número de casos (pelo Joinpoint Regression Program, percentual da mudança anual [APC] = 13,7 - IC95% 4,6;41,5); e entre 1978 e 2019, redução (APC = -6,7 - IC95% -8,8;-5,9). Houve redução da transmissão por cães (71 casos; último caso em 2010) e aumento relativo por mamíferos silvestres (5 casos a partir de 2005). Conclusão: O estudo evidencia mudança na dinâmica da transmissão da raiva no período observado, com redução da transmissão por cão e incremento de casos por animais silvestres.
Objetivo: Describir los casos de la rabia humana en Ceará, Brasil, 1970-2019. Métodos: Estudio descriptivo con datos secundarios de la Secretaría de Salud y del hospital de referencia de Ceará. Resultados: De los 171 casos, 75,7% ocurrió en hombres, el 60,0% en los 19 años y el 56,0% en áreas urbanas. El perro fue transmisor en 74,0%, el mono tití en 16,7% y el murciélago el 7,3%. Entre 1970 y 1978, hubo un aumento de casos (por el Joinpoint Regression Program, cambio porcentual anual [APC] = 13,7 - IC95% 4,6; 41,5), entre 1978 y 2019 una disminución (APC= -6,7 - IC95% -8,8; -5,9). Hubo una reducción de la transmisión por perros (71 casos, el último en 2010) y un aumento por mamíferos salvajes (5 casos, desde 2005). Conclusión: El estudio muestra un cambio en la dinámica de la transmisión de la rabia en los últimos años, con reducción de la transmisión por perros y aumento de casos por animales salvajes.
Objective: To describe cases of human rabies in Ceará State, Brazil between 1970 and 2019. Methods: This was a descriptive study using secondary data from the Ceará State Department of Health and the state reference hospital. Results: Of 171 cases, 75.7% occurred in males, 60.0% in <19-year-olds, and 56.0% in urban areas. Rabies was transmitted by dogs in 74.0% of cases, marmosets in 16.7% and bats in 7.3%. Between 1970 and 1978, there was an increase of cases (using the Joinpoint Regression Program, annual percentage change [APC] = 13.7 - 95%CI 4.6;41.5), while between 1978 and 2019 there was a decrease (APC = -6.7 - 95%CI -8.8;-5.9). There was a reduction in transmission by dogs (71 cases, last case in 2010) and an increase by sylvatic animals (5 cases since 2005). Conclusion: This study demonstrates changes in rabies transmission dynamics during the period studied, with a reduction in transmission by dogs and an increase of transmission by sylvatic animals.
Assuntos
Humanos , Animais , Raiva/transmissão , Raiva/epidemiologia , Zoonoses Virais/epidemiologia , Vírus da Raiva/classificação , Brasil/epidemiologia , Vetores de Doenças , Doenças Negligenciadas , Monitoramento EpidemiológicoRESUMO
In rabies diagnosis, it is essential to count on a rapid test to give a quick response. The combined sensitivity and robustness of the TaqMan RT-PCR assays (qRT-PCR) have made these methods a valuable alternative for rabies virus (RABV) detection. We conducted a study to compare the applicability of two widely used qRT-PCR assays targeting the nucleoprotein gene (LysGT1 assay) and leader sequences (LN34 qRT-PCR assay) of RABV genomes, in all variants circulating in Argentina. A total of 44 samples obtained from bats, dogs, cattle, and horses, that were previously tested for rabies by FAT and conventional RT-PCR, were used in the study. All variants were successfully detected by the pan-lyssavirus LN34 qRT-PCR assay. The LysGT1 assay failed to detect three bat-related variants. We further sequenced the region targeted by LysGT1 and demonstrated that the presence of three or more mismatches with respect to the primers and probe sequences precludes viral detection. We conclude that the LysGT1 assay is prone to yield variant-dependent false-negative test results, and in consequence, the LN34 assay would ensure more effective detection of RABV in Argentina.
Assuntos
Variação Genética , Vírus da Raiva/genética , Raiva/diagnóstico , Raiva/virologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sequência de Aminoácidos , Animais , Argentina/epidemiologia , Bovinos , Quirópteros , Geografia Médica , Cavalos , Humanos , Nucleoproteínas/genética , Filogenia , Filogeografia , RNA Viral , Raiva/epidemiologia , Vírus da Raiva/classificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
As countries with endemic canine rabies progress towards elimination by 2030, it will become necessary to employ techniques to help plan, monitor, and confirm canine rabies elimination. Sequencing can provide critical information to inform control and vaccination strategies by identifying genetically distinct virus variants that may have different host reservoir species or geographic distributions. However, many rabies testing laboratories lack the resources or expertise for sequencing, especially in remote or rural areas where human rabies deaths are highest. We developed a low-cost, high throughput rabies virus sequencing method using the Oxford Nanopore MinION portable sequencer. A total of 259 sequences were generated from diverse rabies virus isolates in public health laboratories lacking rabies virus sequencing capacity in Guatemala, India, Kenya, and Vietnam. Phylogenetic analysis provided valuable insight into rabies virus diversity and distribution in these countries and identified a new rabies virus lineage in Kenya, the first published canine rabies virus sequence from Guatemala, evidence of rabies spread across an international border in Vietnam, and importation of a rabid dog into a state working to become rabies-free in India. Taken together, our evaluation highlights the MinION's potential for low-cost, high volume sequencing of pathogens in locations with limited resources.
Assuntos
Doenças do Cão/virologia , Vírus da Raiva/genética , Raiva/veterinária , Raiva/virologia , Análise de Sequência de DNA/instrumentação , Animais , Equipamentos para Diagnóstico , Cães , Doenças Endêmicas/prevenção & controle , Doenças Endêmicas/veterinária , Guatemala , Humanos , Índia , Quênia , Nanoporos , Filogenia , Saúde Pública , Vírus da Raiva/classificação , Análise de Sequência de DNA/métodos , VietnãRESUMO
Rabies is an important zoonosis worldwide, and this disease is caused by the rabies virus. Dogs and bat are the major hosts of rabies virus; however, many animals could infect with the rabies virus. By biting or scratching by an infected animal, rabies virus can be transmitted to cattle which is an important domestic animal in animal husbandry. Here, we report a case about a rabies virus (abbreviated JSTZ190314) found in cattle in eastern China in 2019. Our findings suggest that this rabies virus JSTZ190314 was a dog-origin rabies virus and belonged to the Asia clade. Furthermore, we found that this JSTZ190314-like rabies virus has been prevalent in China for more than 13 years and infected six species of animals. Our findings suggested that enhanced surveillance and research of rabies virus infection in bovine populations is needed.
Assuntos
Doenças dos Bovinos/virologia , Doenças do Cão/virologia , Filogenia , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Animais , Animais Domésticos/virologia , Bovinos , China , Cães , Raiva/virologia , Vírus da Raiva/classificação , Vírus da Raiva/genética , Sequenciamento Completo do GenomaRESUMO
An unprecedented outbreak of rabies occurred in Rio Grande do Sul state (RS) from 2012 onward, resulting in thousands of bovine deaths, important economic losses, and posing risk to human health. This article describes a genetic analysis of 145 rabies viruses (RABV) recovered from herbivorous from RS between 2012 and 2017, based on partial sequence analysis of the nucleoprotein (N) gene. High nucleotide (nt) identity (95.5 to 100%) and amino acid (aa) similarity (96.7 to 100%) were observed among the analyzed sequences. These sequences displayed a high sequence nt identity/aa similarity with bovine RABV sequences (96.4-97.9%; 98.1-100%, respectively) and vampire bat RABV sequences (96.3-97.5%; 97.8-99.5%). Phylogenetic analyzes based on the N sequence allowed for the segregation of viruses into two distinct clusters. Cluster 1 comprised RABV sequences covering the whole studied period, whereas cluster 2 grouped a lower number of viruses from 2013, 2014, 2015, to 2017. In some cases, viruses obtained from the same region within a short period of time grouped to distinct clusters or sub-clusters, indicating the co-circulation of distinct virus lineages in these outbreaks. The segregation into sub-clusters was also observed for viral sequences obtained from the same region at different times, indicating the involvement of distinct viruses. In summary, partial sequence analyses revealed a high conservation of N protein and the circulation of two lineages and different sublineages of RABV in the region. In addition, our results confirm the suitability of N gene to study the genetic relationships among RABV isolates.
Assuntos
Proteínas do Nucleocapsídeo/genética , Vírus da Raiva/genética , Raiva/veterinária , Animais , Sequência de Bases , Encéfalo/virologia , Brasil/epidemiologia , Bovinos/virologia , Herbivoria , Filogenia , RNA Viral/genética , Raiva/epidemiologia , Raiva/virologia , Vírus da Raiva/classificação , Análise de Sequência , Ovinos/virologiaRESUMO
BACKGROUND: Bats are an important ecological group within ecosystems. The rabies virus is a Lyssavirus, and haematophagous bats are the principal reservoir; however, the virus has also been detected in non-haematophagous bats. The objective was to determine the rabies virus in non-haematophagous bats in the Colombian Caribbean region. METHODS: In 2017, a cross-sectional study was carried out with a base-risk sampling in twelve geographic zones of the Colombian Caribbean area that included the main ecosystems of two departments. 286 bats were captured, which were euthanized with a pharmacological treatment following the ethical protocols of animal experimentation. The taxonomic identification was done with dichotomous keys. The necropsy was carried out at the capture site, and brain samples were kept in liquid nitrogen. The extraction of the RNA was carried out from the frozen brains with Trizol™; a fragment of 914 bp of the glycoprotein G of the rabies virus was amplified with RT-PCR. The amplicons were sequenced with the Sanger method. RESULTS: Twenty-three genera of bats were identified, and, in two frugivorous, Artibeus lituratus and Artibeus planirostris, amplicons were obtained and sequenced as the rabies virus. CONCLUSIONS: This is the first evidence of natural infection of the rabies virus in frugivorous bats in the Colombian Caribbean area; this result is important for the surveillance and control of rabies.