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1.
J Gen Virol ; 99(12): 1590-1599, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29745870

RESUMO

The lyssaviruses are an important group of viruses that cause a fatal encephalitis termed rabies. The prototypic lyssavirus, rabies virus, is predicted to cause more than 60 000 human fatalities annually. The burden of disease for the other lyssaviruses is undefined. The original reports for the recently described highly divergent Lleida bat lyssavirus were based on the detection of virus sequence alone. The successful isolation of live Lleida bat lyssavirus from the carcass of the original bat and in vitro characterization of this novel lyssavirus are described here. In addition, the ability of a human rabies vaccine to confer protective immunity following challenge with this divergent lyssavirus was assessed. Two different doses of Lleida bat lyssavirus were used to challenge vaccinated or naïve mice: a high dose of 100 focus-forming units (f.f.u.) 30 µl-1 and a 100-fold dilution of this dose, 1 f.f.u. 30 µl-1. Although all naïve control mice succumbed to the 100 f.f.u. 30 µl-1 challenge, 42 % (n=5/12) of those infected intracerebrally with 1 f.f.u. 30 µl-1 survived the challenge. In the high-challenge-dose group, 42 % of the vaccinated mice survived the challenge (n=5/12), whilst at the lower challenge dose, 33 % (n=4/12) survived to the end of the experiment. Interestingly, a high proportion of mice demonstrated a measurable virus-neutralizing antibody response, demonstrating that neutralizing antibody titres do not necessarily correlate with the outcome of infection via the intracerebral route. Assessing the ability of existing rabies vaccines to protect against novel divergent lyssaviruses is important for the development of future public health strategies.


Assuntos
Antígenos Virais/imunologia , Quirópteros/virologia , Proteção Cruzada , Lyssavirus/classificação , Lyssavirus/isolamento & purificação , Vacina Antirrábica/imunologia , Infecções por Rhabdoviridae/prevenção & controle , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Modelos Animais de Doenças , Lyssavirus/imunologia , Camundongos , Análise de Sobrevida
2.
Mol Ecol ; 27(3): 773-788, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29274171

RESUMO

Landscape heterogeneity plays an important role in disease spread and persistence, but quantifying landscape influences and their scale dependence is challenging. Studies have focused on how environmental features or global transport networks influence pathogen invasion and spread, but their influence on local transmission dynamics that underpin the persistence of endemic diseases remains unexplored. Bayesian phylogeographic frameworks that incorporate spatial heterogeneities are promising tools for analysing linked epidemiological, environmental and genetic data. Here, we extend these methodological approaches to decipher the relative contribution and scale-dependent effects of landscape influences on the transmission of endemic rabies virus in Serengeti district, Tanzania (area ~4,900 km2 ). Utilizing detailed epidemiological data and 152 complete viral genomes collected between 2004 and 2013, we show that the localized presence of dogs but not their density is the most important determinant of diffusion, implying that culling will be ineffective for rabies control. Rivers and roads acted as barriers and facilitators to viral spread, respectively, and vaccination impeded diffusion despite variable annual coverage. Notably, we found that landscape effects were scale-dependent: rivers were barriers and roads facilitators on larger scales, whereas the distribution of dogs was important for rabies dispersal across multiple scales. This nuanced understanding of the spatial processes that underpin rabies transmission can be exploited for targeted control at the scale where it will have the greatest impact. Moreover, this research demonstrates how current phylogeographic frameworks can be adapted to improve our understanding of endemic disease dynamics at different spatial scales.


Assuntos
Cães/virologia , Vírus da Raiva/fisiologia , Zoonoses/transmissão , Zoonoses/virologia , Animais , Movimento , Filogeografia , Tanzânia
3.
Arch Virol ; 163(8): 2283-2294, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29637429

RESUMO

In 2018, the order Mononegavirales was expanded by inclusion of 1 new genus and 12 novel species. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV) and summarizes additional taxonomic proposals that may affect the order in the near future.


Assuntos
Mononegavirais/classificação , Animais , Humanos , Mononegavirais/genética , Mononegavirais/isolamento & purificação , Infecções por Mononegavirales/veterinária , Infecções por Mononegavirales/virologia , Filogenia
4.
Int J Mol Sci ; 19(1)2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29303971

RESUMO

Bat rabies cases in Europe are mainly attributed to two lyssaviruses, namely European Bat Lyssavirus 1 (EBLV-1) and European Bat Lyssavirus 2 (EBLV-2). Prior to the death of a bat worker in Finland in 1985, very few bat rabies cases were reported. Enhanced surveillance in the two subsequent years (1986-1987) identified 263 cases (more than a fifth of all reported cases to date). Between 1977 and 2016, 1183 cases of bat rabies were reported, with the vast majority (>97%) being attributed to EBLV-1. In contrast, there have been only 39 suspected cases of EBLV-2, of which 34 have been confirmed by virus typing and presently restricted to just two bat species; Myotis daubentonii and Myotis dasycneme. The limited number of EBLV-2 cases in Europe prompted the establishment of a network of European reference laboratories to collate all available viruses and data. Despite the relatively low number of EBLV-2 cases, a large amount of anomalous data has been published in the scientific literature, which we have here reviewed and clarified. In this review, 29 EBLV-2 full genome sequences have been analysed to further our understanding of the diversity and molecular evolution of EBLV-2 in Europe. Analysis of the 29 complete EBLV-2 genome sequences clearly corroborated geographical relationships with all EBLV-2 sequences clustering at the country level irrespective of the gene studied. Further geographical clustering was also observed at a local level. There are high levels of homogeneity within the EBLV-2 species with nucleotide identities ranging from 95.5-100% and amino acid identities between 98.7% and 100%, despite the widespread distribution of the isolates both geographically and chronologically. The mean substitution rate for EBLV-2 across the five concatenated genes was 1.65 × 10-5, and evolutionary clock analysis confirms the slow evolution of EBLV-2 both between and within countries in Europe. This is further supported by the first detailed EBLV-2 intra-roost genomic analysis whereby a relatively high sequence homogeneity was found across the genomes of three EBLV-2 isolates obtained several years apart (2007, 2008, and 2014) from M. daubentonii at the same site (Stokesay Castle, Shropshire, UK).


Assuntos
Evolução Molecular , Lyssavirus/genética , Infecções por Rhabdoviridae/virologia , Animais , Genoma Viral , Humanos , Lyssavirus/classificação , Lyssavirus/isolamento & purificação , Filologia , Infecções por Rhabdoviridae/epidemiologia
5.
BMC Vet Res ; 13(1): 216, 2017 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-28693578

RESUMO

BACKGROUND: In Europe, bat rabies is primarily attributed to European bat lyssavirus type 1 (EBLV-1) and European bat lyssavirus type 2 (EBLV-2) which are both strongly host-specific. Approximately thirty cases of infection with EBLV-2 in Daubenton's bats (Myotis daubentonii) and pond bats (M. dasycneme) have been reported. Two human cases of rabies caused by EBLV-2 have also been confirmed during the last thirty years, while natural spill-over to other non-flying mammals has never been reported. Rabies has never been diagnosed in mainland Norway previously. CASE PRESENTATION: In late September 2015, a subadult male Daubenton's bat was found in a poor condition 800 m above sea level in the southern part of Norway. The bat was brought to the national Bat Care Centre where it eventually displayed signs of neurological disease and died after two days. EBLV-2 was detected in brain tissues by polymerase chain reaction (PCR) followed by sequencing of a part of the nucleoprotein gene, and lyssavirus was isolated in neuroblastoma cells. CONCLUSIONS: The detection of EBLV-2 in a bat in Norway broadens the knowledge on the occurrence of this zoonotic agent. Since Norway is considered free of rabies, adequate information to the general public regarding the possibility of human cases of bat-associated rabies should be given. No extensive surveillance of lyssavirus infections in bats has been conducted in the country, and a passive surveillance network to assess rabies prevalence and bat epidemiology is highly desired.


Assuntos
Quirópteros/virologia , Lyssavirus/isolamento & purificação , Raiva/veterinária , Infecções por Rhabdoviridae/veterinária , Animais , Encéfalo/virologia , Masculino , Noruega/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Raiva/virologia , Infecções por Rhabdoviridae/epidemiologia
6.
PLoS Genet ; 10(6): e1004417, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24901252

RESUMO

Many genes important in immunity are found as multigene families. The butyrophilin genes are members of the B7 family, playing diverse roles in co-regulation and perhaps in antigen presentation. In humans, a fixed number of butyrophilin genes are found in and around the major histocompatibility complex (MHC), and show striking association with particular autoimmune diseases. In chickens, BG genes encode homologues with somewhat different domain organisation. Only a few BG genes have been characterised, one involved in actin-myosin interaction in the intestinal brush border, and another implicated in resistance to viral diseases. We characterise all BG genes in B12 chickens, finding a multigene family organised as tandem repeats in the BG region outside the MHC, a single gene in the MHC (the BF-BL region), and another single gene on a different chromosome. There is a precise cell and tissue expression for each gene, but overall there are two kinds, those expressed by haemopoietic cells and those expressed in tissues (presumably non-haemopoietic cells), correlating with two different kinds of promoters and 5' untranslated regions (5'UTR). However, the multigene family in the BG region contains many hybrid genes, suggesting recombination and/or deletion as major evolutionary forces. We identify BG genes in the chicken whole genome shotgun sequence, as well as by comparison to other haplotypes by fibre fluorescence in situ hybridisation, confirming dynamic expansion and contraction within the BG region. Thus, the BG genes in chickens are undergoing much more rapid evolution compared to their homologues in mammals, for reasons yet to be understood.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Galinhas/genética , Complexo Principal de Histocompatibilidade/genética , Animais , Sequência de Bases , Butirofilinas , Galinhas/sangue , Genoma/genética , Haplótipos/genética , Glicoproteínas de Membrana/genética , Família Multigênica/genética , Análise de Sequência de DNA , Homologia de Sequência , Sequências de Repetição em Tandem/genética
7.
Emerg Infect Dis ; 22(8): 1456-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27434858

RESUMO

A novel lyssavirus was isolated from brains of Indian flying foxes (Pteropus medius) in Sri Lanka. Phylogenetic analysis of complete virus genome sequences, and geographic location and host species, provides strong evidence that this virus is a putative new lyssavirus species, designated as Gannoruwa bat lyssavirus.


Assuntos
Quirópteros/virologia , Lyssavirus/isolamento & purificação , Infecções por Rhabdoviridae/veterinária , Animais , Feminino , Genoma Viral , Lyssavirus/genética , Masculino , Filogenia , Infecções por Rhabdoviridae/epidemiologia , Infecções por Rhabdoviridae/virologia , Sri Lanka/epidemiologia
8.
J Gen Virol ; 97(5): 1060-1065, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26932442

RESUMO

Hantaviruses are emerging zoonotic viruses that cause human diseases. In this study, sera from 642 mammals from La Réunion and Mayotte islands (Indian Ocean) were screened for the presence of hantaviruses by molecular analysis. None of the mammals from La Réunion island was positive, but hantavirus genomic RNA was discovered in 29/160 (18 %) Rattus rattus from Mayotte island. The nucleoprotein coding region was sequenced from the liver and spleen of all positive individuals allowing epidemiological and intra-strain variability analyses. Phylogenetic analysis based on complete coding genomic sequences showed that this Murinae-associated hantavirus is a new variant of Thailand virus. Further studies are needed to investigate hantaviruses in rodent hosts and in Haemorrhagic Fever with Renal Syndrome (HFRS) human cases.


Assuntos
Infecções por Hantavirus/veterinária , Orthohantavírus/isolamento & purificação , Ratos , Doenças dos Roedores/virologia , Animais , Comores/epidemiologia , Feminino , Variação Genética , Orthohantavírus/classificação , Orthohantavírus/genética , Infecções por Hantavirus/epidemiologia , Infecções por Hantavirus/virologia , Masculino , Filogenia , Doenças dos Roedores/epidemiologia
9.
Emerg Infect Dis ; 21(5): 879-82, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25898126

RESUMO

Genetic sequences of a highly pathogenic avian influenza (H5N8) virus in England have high homology to those detected in mainland Europe and Asia during 2014. Genetic characterization suggests this virus is an avian-adapted virus without specific affinity for zoonoses. Spatio-temporal detections of H5N8 imply a role for wild birds in virus spread.


Assuntos
Patos/virologia , Genoma Viral , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Animais , Inglaterra/epidemiologia , Genes Virais , Genótipo , História do Século XXI , Vírus da Influenza A/patogenicidade , Influenza Aviária/história , Mutação , Fenótipo , Filogenia
10.
J Gen Virol ; 95(Pt 5): 1025-1032, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24496827

RESUMO

In 2009, a novel lyssavirus (subsequently named Ikoma lyssavirus, IKOV) was detected in the brain of an African civet (Civettictis civetta) with clinical rabies in the Serengeti National Park of Tanzania. The degree of nucleotide divergence between the genome of IKOV and those of other lyssaviruses predicted antigenic distinction from, and lack of protection provided by, available rabies vaccines. In addition, the index case was considered likely to be an incidental spillover event, and therefore the true reservoir of IKOV remained to be identified. The advent of sensitive molecular techniques has led to a rapid increase in the discovery of novel viruses. Detecting viral sequence alone, however, only allows for prediction of phenotypic characteristics and not their measurement. In the present study we describe the in vitro and in vivo characterization of IKOV, demonstrating that it is (1) pathogenic by peripheral inoculation in an animal model, (2) antigenically distinct from current rabies vaccine strains and (3) poorly neutralized by sera from humans and animals immunized against rabies. In a laboratory mouse model, no protection was elicited by a licensed rabies vaccine. We also investigated the role of bats as reservoirs of IKOV. We found no evidence for infection among 483 individuals of at least 13 bat species sampled across sites in the Serengeti and Southern Kenya.


Assuntos
Antígenos Virais/genética , Antígenos Virais/imunologia , Lyssavirus/genética , Lyssavirus/imunologia , Infecções por Rhabdoviridae/veterinária , Animais , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Quênia , Lyssavirus/classificação , Lyssavirus/isolamento & purificação , Camundongos , Vacina Antirrábica/imunologia , Infecções por Rhabdoviridae/virologia , Tanzânia , Viverridae
11.
Virol J ; 11: 32, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24555484

RESUMO

BACKGROUND: Hantaviruses are single-stranded RNA viruses, which are transmitted to humans primarily via inhalation of aerosolised virus in contaminated rodent urine and faeces. Whilst infected reservoir hosts are asymptomatic, human infections can lead to two clinical manifestations, haemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS), with varying degrees of clinical severity. The incidence of rodent and human cases of Seoul virus (SEOV) in Europe has been considered to be low, and speculated to be driven by the sporadic introduction of infected brown rats (Rattus norvegicus) via ports. METHODS: Between October 2010 and March 2012, 128 brown rats were caught at sites across the Lyon region in France. RESULTS: SEOV RNA was detected in the lungs of 14% (95% CI 8.01-20.11) of brown rats tested using a nested pan-hantavirus RT-PCR (polymerase gene). Phylogenetic analysis supports the inclusion of the Lyon SEOV within Lineage 7 with SEOV strains originating from SE Asia and the previously reported French & Belgian SEOV strains. Sequence data obtained from the recent human SEOV case (Replonges) was most similar to that obtained from one brown rat trapped in a public park in Lyon city centre. We obtained significantly improved recovery of virus genome sequence directly from SEOV infected lung material using a simple viral enrichment approach and NGS technology. CONCLUSIONS: The detection of SEOV in two wild caught brown rats in the UK and the multiple detection of SEOV infected brown rats in the Lyon region of France, suggests that SEOV is circulating in European brown rats. Under-reporting and difficulties in identifying the hantaviruses associated with HFRS may mask the public health impact of SEOV in Europe.


Assuntos
Portador Sadio/veterinária , Reservatórios de Doenças , Ratos/virologia , Vírus Seoul/isolamento & purificação , Animais , Portador Sadio/epidemiologia , Portador Sadio/virologia , Análise por Conglomerados , França/epidemiologia , Pulmão/virologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência
12.
BMC Genomics ; 14: 444, 2013 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-23822119

RESUMO

BACKGROUND: With the advent of Next Generation Sequencing (NGS) technologies, the ability to generate large amounts of sequence data has revolutionized the genomics field. Most RNA viruses have relatively small genomes in comparison to other organisms and as such, would appear to be an obvious success story for the use of NGS technologies. However, due to the relatively low abundance of viral RNA in relation to host RNA, RNA viruses have proved relatively difficult to sequence using NGS technologies. Here we detail a simple, robust methodology, without the use of ultra-centrifugation, filtration or viral enrichment protocols, to prepare RNA from diagnostic clinical tissue samples, cell monolayers and tissue culture supernatant, for subsequent sequencing on the Roche 454 platform. RESULTS: As representative RNA viruses, full genome sequence was successfully obtained from known lyssaviruses belonging to recognized species and a novel lyssavirus species using these protocols and assembling the reads using de novo algorithms. Furthermore, genome sequences were generated from considerably less than 200 ng RNA, indicating that manufacturers' minimum template guidance is conservative. In addition to obtaining genome consensus sequence, a high proportion of SNPs (Single Nucleotide Polymorphisms) were identified in the majority of samples analyzed. CONCLUSIONS: The approaches reported clearly facilitate successful full genome lyssavirus sequencing and can be universally applied to discovering and obtaining consensus genome sequences of RNA viruses from a variety of sources.


Assuntos
Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de RNA/métodos , Animais , Sequência de Bases , Encéfalo/virologia , Linhagem Celular , Cricetinae , Heterogeneidade Genética , Lyssavirus/genética , Camundongos , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , RNA Viral/genética , Cultura de Vírus
13.
J Gen Virol ; 94(Pt 2): 284-292, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23100360

RESUMO

European bat lyssaviruses type 1 (EBLV-1) and type 2 (EBLV-2) circulate within bat populations throughout Europe and are capable of causing disease indistinguishable from that caused by classical rabies virus (RABV). However, the determinants of viral fitness and pathogenicity are poorly understood. Full-length genome clones based on the highly attenuated, non-neuroinvasive, RABV vaccine strain (SAD-B19) were constructed with the glycoprotein (G) of either SAD-B19 (SN), of EBLV-1 (SN-1) or EBLV-2 (SN-2). In vitro characterization of SN-1 and SN-2 in comparison to wild-type EBLVs demonstrated that the substitution of G affected the final virus titre and antigenicity. In vivo, following peripheral infection with a high viral dose (10(4) f.f.u.), animals infected with SN-1 had reduced survivorship relative to infection with SN, resulting in survivorship similar to animals infected with EBLV-1. The histopathological changes and antigen distribution observed for SN-1 were more representative of those observed with SN than with EBLV-1. EBLV-2 was unable to achieve a titre equivalent to that of the other viruses. Therefore, a reduced-dose experiment (10(3) f.f.u.) was undertaken in vivo to compare EBLV-2 and SN-2, which resulted in 100 % survivorship for all recombinant viruses (SN, SN-1 and SN-2) while clinical disease developed in mice infected with the EBLVs. These data indicate that interspecies replacement of G has an effect on virus titre in vitro, probably as a result of suboptimal G-matrix protein interactions, and influences the survival outcome following a peripheral challenge with a high virus titre in mice.


Assuntos
Glicoproteínas/metabolismo , Lyssavirus/genética , Lyssavirus/patogenicidade , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismo , Animais , Antígenos Virais/genética , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Modelos Animais de Doenças , Glicoproteínas/genética , Glicoproteínas/imunologia , Histocitoquímica , Imuno-Histoquímica , Lyssavirus/imunologia , Camundongos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Recombinação Genética , Infecções por Rhabdoviridae/patologia , Infecções por Rhabdoviridae/virologia , Análise de Sobrevida , Carga Viral , Proteínas Virais/genética , Proteínas Virais/imunologia , Fatores de Virulência/genética , Fatores de Virulência/imunologia
14.
J Gen Virol ; 94(Pt 1): 69-75, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23100368

RESUMO

Rhabdoviruses infect a variety of hosts, including mammals, birds, reptiles, fish, insects and plants. As bats are the natural host for most members of the genus Lyssavirus, the specificity of the amplification methods used for active surveillance is usually restricted to lyssaviruses. However, the presence of other rhabdoviruses in bats has also been reported. In order to broaden the scope of such methods, a new RT-PCR, able to detect a diverse range of rhabdoviruses, was designed. The method detected 81 of 86 different rhabdoviruses. In total, 1488 oropharyngeal bat swabs and 38 nycteribiid samples were analysed, and 17 unique rhabdovirus-related sequences were detected. Phylogenetic analysis suggested that those sequences detected in bats did not constitute a monophyletic group, even when originating from the same bat species. However, all of the sequences detected in nycteribiids and one sequence obtained from a bat did constitute a monophyletic group with Drosophila melanogaster sigma rhabdovirus.


Assuntos
Quirópteros/virologia , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Rhabdoviridae/genética , Rhabdoviridae/isolamento & purificação , Animais , Drosophila melanogaster/virologia , Insetos/virologia , Orofaringe/virologia , Filogenia , Infecções por Rhabdoviridae/genética , Infecções por Rhabdoviridae/virologia
15.
J Virol ; 86(18): 10242-3, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22923801

RESUMO

Lyssaviruses (family Rhabdoviridae) constitute one of the most important groups of viral zoonoses globally. All lyssaviruses cause the disease rabies, an acute progressive encephalitis for which, once symptoms occur, there is no effective cure. Currently available vaccines are highly protective against the predominantly circulating lyssavirus species. Using next-generation sequencing technologies, we have obtained the whole-genome sequence for a novel lyssavirus, Ikoma lyssavirus (IKOV), isolated from an African civet in Tanzania displaying clinical signs of rabies. Genetically, this virus is the most divergent within the genus Lyssavirus. Characterization of the genome will help to improve our understanding of lyssavirus diversity and enable investigation into vaccine-induced immunity and protection.


Assuntos
Lyssavirus/genética , Animais , Genoma Viral , Lyssavirus/classificação , Lyssavirus/isolamento & purificação , Lyssavirus/patogenicidade , Dados de Sequência Molecular , RNA Viral/genética , Infecções por Rhabdoviridae/veterinária , Infecções por Rhabdoviridae/virologia , Tanzânia , Viverridae/virologia , Zoonoses/virologia
16.
Front Public Health ; 11: 1121522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37383258

RESUMO

Introduction: The awareness of scientists and policy makers regarding the requirement for an integrated One Health (OH) approach in responding to zoonoses has increased in recent years. However, there remains an overall inertia in relation to the implementation of practical cross-sector collaborations. Foodborne outbreaks of zoonotic diseases continue to affect the European population despite stringent regulations, evidencing the requirement for better 'prevent, detect and response' strategies. Response exercises play an essential role in the improvement of crisis management plans, providing the opportunity to test practical intervention methodologies in a controlled environment. Methods: The One Health European Joint Programme simulation exercise (OHEJP SimEx) aimed at practicing the OH capacity and interoperability across public health, animal health and food safety sectors in a challenging outbreak scenario. The OHEJP SimEx was delivered through a sequence of scripts covering the different stages of a Salmonella outbreak investigation at a national level, involving both the human food chain and the raw pet feed industry. Results: A total of 255 participants from 11 European countries (Belgium, Denmark, Estonia, Finland, France, Italy, Norway, Poland, Portugal, Sweden, the Netherlands) took part in national level two-day exercises during 2022. National evaluations identified common recommendations to countries aiming to improve their OH structure to establish formal communication channels between sectors, implement a common data sharing platform, harmonize laboratory procedures, and reinforce inter-laboratory networks within countries. The large proportion of participants (94%) indicated significant interest in pursuing a OH approach and desire to work more closely with other sectors. Discussion: The OHEJP SimEx outcomes will assist policy makers in implementing a harmonized approach to cross-sector health-related topics, by highlighting the benefits of cooperation, identifying gaps in the current strategies and suggesting actions required to better address foodborne outbreaks. Furthermore, we summarize recommendations for future OH simulation exercises, which are essential to continually test, challenge and improve national OH strategies.


Assuntos
Saúde Única , Animais , Humanos , Disseminação de Informação , Comunicação , Exercício Físico , Zoonoses , Surtos de Doenças/prevenção & controle
17.
Elife ; 122023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37227428

RESUMO

Background: Dog-mediated rabies is endemic across Africa causing thousands of human deaths annually. A One Health approach to rabies is advocated, comprising emergency post-exposure vaccination of bite victims and mass dog vaccination to break the transmission cycle. However, the impacts and cost-effectiveness of these components are difficult to disentangle. Methods: We combined contact tracing with whole-genome sequencing to track rabies transmission in the animal reservoir and spillover risk to humans from 2010 to 2020, investigating how the components of a One Health approach reduced the disease burden and eliminated rabies from Pemba Island, Tanzania. With the resulting high-resolution spatiotemporal and genomic data, we inferred transmission chains and estimated case detection. Using a decision tree model, we quantified the public health burden and evaluated the impact and cost-effectiveness of interventions over a 10-year time horizon. Results: We resolved five transmission chains co-circulating on Pemba from 2010 that were all eliminated by May 2014. During this period, rabid dogs, human rabies exposures and deaths all progressively declined following initiation and improved implementation of annual islandwide dog vaccination. We identified two introductions to Pemba in late 2016 that seeded re-emergence after dog vaccination had lapsed. The ensuing outbreak was eliminated in October 2018 through reinstated islandwide dog vaccination. While post-exposure vaccines were projected to be highly cost-effective ($256 per death averted), only dog vaccination interrupts transmission. A combined One Health approach of routine annual dog vaccination together with free post-exposure vaccines for bite victims, rapidly eliminates rabies, is highly cost-effective ($1657 per death averted) and by maintaining rabies freedom prevents over 30 families from suffering traumatic rabid dog bites annually on Pemba island. Conclusions: A One Health approach underpinned by dog vaccination is an efficient, cost-effective, equitable, and feasible approach to rabies elimination, but needs scaling up across connected populations to sustain the benefits of elimination, as seen on Pemba, and for similar progress to be achieved elsewhere. Funding: Wellcome [207569/Z/17/Z, 095787/Z/11/Z, 103270/Z/13/Z], the UBS Optimus Foundation, the Department of Health and Human Services of the National Institutes of Health [R01AI141712] and the DELTAS Africa Initiative [Afrique One-ASPIRE/DEL-15-008] comprising a donor consortium of the African Academy of Sciences (AAS), Alliance for Accelerating Excellence in Science in Africa (AESA), the New Partnership for Africa's Development Planning and Coordinating (NEPAD) Agency, Wellcome [107753/A/15/Z], Royal Society of Tropical Medicine and Hygiene Small Grant 2017 [GR000892] and the UK government. The rabies elimination demonstration project from 2010-2015 was supported by the Bill & Melinda Gates Foundation [OPP49679]. Whole-genome sequencing was partially supported from APHA by funding from the UK Department for Environment, Food and Rural Affairs (Defra), Scottish government and Welsh government under projects SEV3500 and SE0421.


Assuntos
Mordeduras e Picadas , Doenças do Cão , Vacina Antirrábica , Raiva , Cães , Animais , Humanos , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária , Busca de Comunicante , Análise Custo-Benefício , Vacina Antirrábica/genética , Tanzânia/epidemiologia , Genômica , Mordeduras e Picadas/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/prevenção & controle
18.
Emerg Infect Dis ; 18(4): 664-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22469151

RESUMO

Evidence in support of a novel lyssavirus was obtained from brain samples of an African civet in Tanzania. Results of phylogenetic analysis of nucleoprotein gene sequences from representative Lyssavirus species and this novel lyssavirus provided strong empirical evidence that this is a new lyssavirus species, designated Ikoma lyssavirus.


Assuntos
Lyssavirus/isolamento & purificação , Raiva/veterinária , Raiva/virologia , Viverridae/virologia , Animais , Teorema de Bayes , Humanos , Lyssavirus/classificação , Lyssavirus/genética , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Tanzânia
19.
Adv Virus Res ; 112: 115-173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35840180

RESUMO

Rabies infects all mammals; however, transmission cycles are only maintained in certain bat and carnivore species. The high incidence of rabies in Greater Kudu (Tragelaphus strepsiceros) observed in Namibia for over 40 years has led to postulation that independent virus transmission is occurring within this antelope population. We have analysed extensive experimental, epidemiological, phylogeographic and deep sequence data, which collectively refute maintenance of an independent rabies cycle in kudu. As rabies in kudu continues to have a negative impact on the Namibian agricultural sector, measures to protect kudu have been investigated, including the use of a third-generation oral rabies vaccine. Initial results show protection of kudu from rabies infection via the oral route, with an appropriate bait design, different application schedules and vaccination doses further enhancing the immune response. Rabies in kudu is a complex interplay at the wildlife-livestock interface and requires a concerted approach to successfully control.


Assuntos
Antílopes , Vacina Antirrábica , Vírus da Raiva , Raiva , Animais , Animais Selvagens , Antílopes/fisiologia , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária , Vírus da Raiva/genética
20.
Front Vet Sci ; 8: 728271, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660765

RESUMO

Background: Thermostable vaccines greatly improved the reach and impact of large-scale programmes to eliminate infectious diseases such as smallpox, polio, and rinderpest. A study from 2015 demonstrated that the potency of the Nobivac® Rabies vaccine was not impacted following experimental storage at 30°C for 3 months. Whether the vaccine would remain efficacious following storage under more natural, fluctuating temperature conditions remains unknown. We carried out a randomised controlled non-inferiority trial to compare serological responses in dogs following vaccination with doses stored under cold chain conditions with those stored within a locally made Passive Cooling Device ("Zeepot") under fluctuating temperature conditions. Materials and Methods: Nobivac® Rabies vaccine was stored under either cold-chain conditions or within the Zeepot for 2 months. Daily ambient temperatures and temperatures within the Zeepot were recorded every 3 h. Following storage, 412 domestic dogs were randomly assigned to receive either cold-chain or Zeepot stored Nobivac® Rabies vaccine. Baseline and day 28-post vaccination blood samples were collected. Serological analysis using the Fluorescent Antibody Virus Neutralisation assay was carried out with a threshold of 0.5 IU/ml to determine seroconversion. In addition, the impact of dog Body Condition Score, sex, and age on seroconversion was examined. Results: The serological response of dogs vaccinated using Nobivac® Rabies vaccine stored within the Zeepot was not inferior to the response of dogs vaccinated using cold-chain stored vaccine (z = 1.1, df = 313, p-value = 0.25). Indeed, the 28-day post-vaccination group geometric mean titre was 1.8 and 2.0 IU/ml for cold-chain vs. non-cold-chain storage, respectively. Moreover, the percentage of dogs that seroconverted in each arm was almost identical (85%). There was a positive linear trend between Body Condition Score (O.R. 2.2, 95% CI: 1.1-5.1) and seroconversion, suggesting dogs of poor condition may not respond as expected to vaccination. Conclusions: Our study demonstrated the potency of Nobivac® Rabies vaccine is not impacted following storage under elevated fluctuating temperatures within a Zeepot. These results have potentially exciting applications for scaling up mass dog vaccination programmes in low-and-middle income countries, particularly for hard-to-reach populations with limited access to power and cold-chain vaccine storage.

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