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1.
Nature ; 598(7882): 652-656, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34646009

RESUMO

Humans are considered as the main host for Mycobacterium leprae1, the aetiological agent of leprosy, but spillover has occurred to other mammals that are now maintenance hosts, such as nine-banded armadillos and red squirrels2,3. Although naturally acquired leprosy has also been described in captive nonhuman primates4-7, the exact origins of infection remain unclear. Here we describe leprosy-like lesions in two wild populations of western chimpanzees (Pan troglodytes verus) in Cantanhez National Park, Guinea-Bissau and Taï National Park, Côte d'Ivoire, West Africa. Longitudinal monitoring of both populations revealed the progression of disease symptoms compatible with advanced leprosy. Screening of faecal and necropsy samples confirmed the presence of M. leprae as the causative agent at each site and phylogenomic comparisons with other strains from humans and other animals show that the chimpanzee strains belong to different and rare genotypes (4N/O and 2F). These findings suggest that M. leprae may be circulating in more wild animals than suspected, either as a result of exposure to humans or other unknown environmental sources.

2.
Viruses ; 13(9)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34578330

RESUMO

Influenza D virus (IDV) was first isolated in 2011 in Oklahoma, USA from pigs presenting with influenza-like symptoms. IDV is known to mainly circulate in ruminants, especially cattle. In Africa, there is limited information on the epidemiology of IDV, although the virus has likely circulated in the region since 2012. In the present study, we investigated the seropositivity of IDV among domestic ruminants and swine in West and East Africa from 2017 to 2020. Serum samples were analyzed using the hemagglutination inhibition (HI) assay. Our study demonstrated that IDV is still circulating in Africa, with variations in seropositivity among countries and species. The highest seropositivity was detected in cattle (3.9 to 20.9%). Our data highlights a need for extensive surveillance of IDV in Africa in order to better understand the epidemiology of the virus in the region.

3.
Vet World ; 14(7): 1727-1740, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34475692

RESUMO

For decades, Newcastle disease (ND) has long been recognized as a frontline viral disease that constrains poultry production throughout Africa. The need to update on the epidemiology of the disease is rife, due to the increasing importance of poultry farming. In addition, poultry farming serves as the top animal food source globally. However, in Africa, the greater population of poultry is reared under traditional and conventional husbandry methods. This hugely impedes the ability of management practices to be correctly embraced in limiting or excluding viral pathogens in the poultry production chain. We conducted this review to consolidate recently published studies in the field and provide an overview of the disease. We reviewed original studies conducted on ND, the current taxonomic classification of the virus, clinical signs of the disease, and laboratory diagnostic methods available for virus detection and typing. This review additionally examined the control methods currently used, including available or circulating vaccines, vaccinations, recent vaccine findings, and the main variants of the virus present in West Africa. More specifically, we present a review of the current status and available information on the disease in Côte d'Ivoire. The lack of up-to-date and relevant information on the current prevalence, socio-economic impact, and ethnoveterinary medicine used against ND is probably the main limitation for appropriate and effective decision-making for better control of this disease in Côte d'Ivoire.

4.
BMC Infect Dis ; 21(1): 539, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34098893

RESUMO

BACKGROUND: In sub-Saharan Africa, acute respiratory infections (ARI), acute gastrointestinal infections (GI) and acute febrile disease of unknown cause (AFDUC) have a large disease burden, especially among children, while respective aetiologies often remain unresolved. The need for robust infectious disease surveillance to detect emerging pathogens along with common human pathogens has been highlighted by the ongoing novel coronavirus disease 2019 (COVID-19) pandemic. The African Network for Improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA) is a sentinel surveillance study on the aetiology and clinical characteristics of ARI, GI and AFDUC in sub-Saharan Africa. METHODS: ANDEMIA includes 12 urban and rural health care facilities in four African countries (Côte d'Ivoire, Burkina Faso, Democratic Republic of the Congo and Republic of South Africa). It was piloted in 2018 in Côte d'Ivoire and the initial phase will run from 2019 to 2021. Case definitions for ARI, GI and AFDUC were established, as well as syndrome-specific sampling algorithms including the collection of blood, naso- and oropharyngeal swabs and stool. Samples are tested using comprehensive diagnostic protocols, ranging from classic bacteriology and antimicrobial resistance screening to multiplex real-time polymerase chain reaction (PCR) systems and High Throughput Sequencing. In March 2020, PCR testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and analysis of full genomic information was included in the study. Standardised questionnaires collect relevant clinical, demographic, socio-economic and behavioural data for epidemiologic analyses. Controls are enrolled over a 12-month period for a nested case-control study. Data will be assessed descriptively and aetiologies will be evaluated using a latent class analysis among cases. Among cases and controls, an integrated analytic approach using logistic regression and Bayesian estimation will be employed to improve the assessment of aetiology and associated risk factors. DISCUSSION: ANDEMIA aims to expand our understanding of ARI, GI and AFDUC aetiologies in sub-Saharan Africa using a comprehensive laboratory diagnostics strategy. It will foster early detection of emerging threats and continued monitoring of important common pathogens. The network collaboration will be strengthened and site diagnostic capacities will be reinforced to improve quality management and patient care.


Assuntos
Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/epidemiologia , Programas de Rastreamento , Vigilância de Evento Sentinela , Teorema de Bayes , Burkina Faso , Estudos de Casos e Controles , Costa do Marfim , República Democrática do Congo , Febre/epidemiologia , Febre/microbiologia , Gastroenteropatias/epidemiologia , Gastroenteropatias/microbiologia , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/epidemiologia , África do Sul
5.
PLoS Negl Trop Dis ; 14(10): e0008699, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33095766

RESUMO

Surveillance of highly pathogenic viruses circulating in both human and animal populations is crucial to unveil endemic infections and potential zoonotic reservoirs. Monitoring the burden of disease by serological assay could be used as an early warning system for imminent outbreaks as an increased seroprevalance often precedes larger outbreaks. However, the multitude of highly pathogenic viruses necessitates the need to identify specific antibodies against several targets from both humans as well as from potential reservoir animals such as bats. In order to address this, we have developed a broadly reactive multiplex microsphere immunoassay (MMIA) for the detection of antibodies against several highly pathogenic viruses from both humans and animals. To this aim, nucleoproteins (NP) of Ebola virus (EBOV), Marburg virus (MARV) and nucleocapsid proteins (NP) of Crimean-Congo haemorrhagic fever virus, Rift Valley fever virus and Dobrava-Belgrade hantavirus were employed in a 5-plex assay for IgG detection. After optimisation, specific binding to each respective NP was shown by testing sera from humans and non-human primates with known infection status. The usefulness of our assay for serosurveillance was shown by determining the immune response against the NP antigens in a panel of 129 human serum samples collected in Guinea between 2011 and 2012 in comparison to a panel of 88 sera from the German blood bank. We found good agreement between our MMIA and commercial or in-house reference methods by ELISA or IIFT with statistically significant higher binding to both EBOV NP and MARV NP coupled microspheres in the Guinea panel. Finally, the MMIA was successfully adapted to detect antibodies from bats that had been inoculated with EBOV- and MARV- virus-like particles, highlighting the versatility of this technique and potentially enabling the monitoring of wildlife as well as human populations with this assay. We were thus able to develop and validate a sensitive and broadly reactive high-throughput serological assay which could be used as a screening tool to detect antibodies against several highly pathogenic viruses.


Assuntos
Anticorpos Antivirais/sangue , Imunoensaio/métodos , Microesferas , Proteínas do Nucleocapsídeo/imunologia , Viroses/veterinária , Animais , Quirópteros , Humanos , Primatas , Viroses/diagnóstico , Viroses/virologia
6.
Arch Virol ; 165(10): 2291-2299, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32754877

RESUMO

The multimammate mouse (Mastomys natalensis; M. natalensis) serves as the main reservoir for the zoonotic arenavirus Lassa virus (LASV), and this has led to considerable investigation into the distribution of LASV and other related arenaviruses in this host species. In contrast to the situation with arenaviruses, the presence of other viruses in M. natalensis remains largely unexplored. In this study, herpesviruses and polyomaviruses were identified and partially characterized by PCR methods, sequencing, and phylogenetic analysis. In tissues sampled from M. natalensis populations in Côte d'Ivoire and Mali, six new DNA viruses (four betaherpesviruses, one gammaherpesvirus and one polyomavirus) were identified. Phylogenetic analysis based on glycoprotein B amino acid sequences showed that the herpesviruses clustered with cytomegaloviruses and rhadinoviruses of multiple rodent species. The complete circular genome of the newly identified polyomavirus was amplified by PCR. Amino acid sequence analysis of the large T antigen or VP1 showed that this virus clustered with a known polyomavirus from a house mouse (species Mus musculus polyomavirus 1). These two polyomaviruses form a clade with other rodent polyomaviruses, and the newly identified virus represents the third known polyomavirus of M. natalensis. This study represents the first identification of herpesviruses and the discovery of a novel polyomavirus in M. natalensis. In contrast to arenaviruses, we anticipate that these newly identified viruses represent a low zoonotic risk due to the normally highly restricted specificity of members of these two DNA virus families to their individual mammalian host species.


Assuntos
Genoma Viral , Infecções por Herpesviridae/epidemiologia , Herpesviridae/genética , Filogenia , Infecções por Polyomavirus/epidemiologia , Polyomavirus/genética , Doenças dos Roedores/epidemiologia , África ao Sul do Saara/epidemiologia , Animais , Antígenos Virais de Tumores/genética , Proteínas do Capsídeo/genética , Reservatórios de Doenças/virologia , Herpesviridae/classificação , Herpesviridae/isolamento & purificação , Infecções por Herpesviridae/virologia , Especificidade de Hospedeiro , Tipagem Molecular , Murinae/virologia , Polyomavirus/classificação , Polyomavirus/isolamento & purificação , Infecções por Polyomavirus/virologia , Doenças dos Roedores/virologia , Proteínas do Envelope Viral/genética
7.
J Vis Exp ; (160)2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32658185

RESUMO

Functional rabies surveillance systems are crucial to provide reliable data and increase the political commitment necessary for disease control. To date, animals suspected as rabies-positive must be submitted to a postmortem confirmation using classical or molecular laboratory methods. However, most endemic areas are in low- and middle-income countries where animal rabies diagnosis is restricted to central veterinary laboratories. Poor availability of surveillance infrastructure leads to serious disease underreporting from remote areas. Several diagnostic protocols requiring low technical expertise have been recently developed, providing opportunity to establish rabies diagnosis in decentralized laboratories. We present here a complete protocol for field postmortem diagnosis of animal rabies using a rapid immunochromatographic diagnostic test (RIDT), from brain biopsy sampling to the final interpretation. We complete the protocol by describing a further use of the device for molecular analysis and viral genotyping. RIDT easily detects rabies virus and other lyssaviruses in brain samples. The principle of such tests is simple: brain material is applied on a test strip where gold conjugated antibodies bind specifically to rabies antigens. The antigen-antibody complexes bind further to fixed antibodies on the test line, resulting in a clearly visible purple line. The virus is inactivated in the test strip, but viral RNA can be subsequently extracted. This allows the test strip, rather than the infectious brain sample, to be safely and easily sent to an equipped laboratory for confirmation and molecular typing. Based on a modification of the manufacturer's protocol, we found increased test sensitivity, reaching 98% compared to the gold standard reference method, the direct immunofluorescence antibody test. The advantages of the test are numerous: rapid, easy-to-use, low cost and no requirement for laboratory infrastructure, such as microscopy or cold-chain compliance. RIDTs represent a useful alternative for areas where reference diagnostic methods are not available.


Assuntos
Testes Diagnósticos de Rotina/métodos , Vírus da Raiva/imunologia , Raiva/imunologia , Animais , Diagnóstico , Imunoensaio , Raiva/veterinária
8.
PLoS Negl Trop Dis ; 14(5): e0008292, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32407387

RESUMO

Bacillus cereus biovar anthracis (Bcbva) is an untypical anthrax-causing pathogen responsible for high wildlife mortality in Taï National Park (TNP), Côte d'Ivoire. However, nothing is known about its effect on the rural population living in the region bordering TNP. Contact to bushmeat is a known risk factor for exposure to a variety of zoonotic pathogens, but no human infections with Bcbva were noted so far. Therefore, we performed a retrospective seroprevalence analysis with sera from 1,386 study volunteers. We used assays which detect antibodies against the protective antigen PA, which is synthesized by both Bcbva and classic B. anthracis, and against the recently described antigen pXO2-60, a 35-kDa protein only produced by Bcbva. We found a high seroprevalence (22.37%) of antibodies against PA, and approximately half of those sera (10.46%) were also positive for the Bcbva-specific antigen pXO2-60. All sera negative for PA were also negative for antibodies against pXO2-60, confirming specificity and suitability of the PA/pXO2-60 combined serological assay. The fact that a large fraction of sera was positive for PA but negative for pXO2-60 can most likely be explained by lower immunogenicity of pXO2-60, but exposure to classic B. anthracis cannot be excluded. As only Bcbva has been detected in the TNP area so far, exposure to Bcbva can be suspected from the presence of antibodies against PA alone. In a questionnaire, most study participants reported contact to bushmeat and livestock carcasses. Unfortunately, risk factor analysis indicated that neither animal contacts, sex, age, nor country of origin were significant predictors of Bcbva seroprevalence. Nevertheless, our study added to an assessment of the distribution of Bcbva and its impact on the human population, and our data can serve to raise awareness of anthrax in the affected regions.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Bacillus cereus/imunologia , Exposição Ambiental , Parques Recreativos , População Rural , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Costa do Marfim , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Inquéritos e Questionários , Adulto Jovem
9.
Nat Microbiol ; 5(7): 955-965, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32341480

RESUMO

Monkeypox is a viral zoonotic disease on the rise across endemic habitats. Despite the growing importance of monkeypox virus, our knowledge on its host spectrum and sylvatic maintenance is limited. Here, we describe the recent repeated emergence of monkeypox virus in a wild, human-habituated western chimpanzee (Pan troglodytes verus, hereafter chimpanzee) population from Taï National Park, Ivory Coast. Through daily monitoring, we show that further to causing its typical exanthematous syndrome, monkeypox can present itself as a severe respiratory disease without a diffuse rash. By analysing 949 non-invasively collected samples, we identify the circulation of at least two distinct monkeypox virus lineages and document the shedding of infectious particles in faeces and flies, suggesting that they could mediate indirect transmission. We also show that the carnivorous component of the Taï chimpanzees' diet, mainly consisting of the sympatric monkeys they regularly hunt, did not change nor shift towards rodent consumption (the presumed reservoir) before the outbreaks, suggesting that the sudden emergence of monkeypox virus in this population is probably due to changes in the ecology of the virus itself. Using long-term mortality surveillance data from Taï National Park, we provide evidence of little to no prior viral activity over at least two decades. We conclude that great ape sentinel systems devoted to the longitudinal collection of behavioural and health data can help clarify the epidemiology and clinical presentation of zoonotic pathogens.


Assuntos
Animais Selvagens , Vírus da Varíola dos Macacos/fisiologia , Monkeypox/virologia , Pan troglodytes/virologia , Animais , Ecossistema , Exantema/etiologia , Exantema/metabolismo , Exantema/patologia , Espaço Extracelular/metabolismo , Fezes/virologia , Genoma Viral , Genômica/métodos , Glutationa/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Monkeypox/complicações , Monkeypox/metabolismo , Monkeypox/mortalidade , Vírus da Varíola dos Macacos/classificação , Vírus da Varíola dos Macacos/isolamento & purificação , Pan troglodytes/metabolismo , Filogenia , Transtornos Respiratórios/etiologia , Transtornos Respiratórios/metabolismo
10.
PLoS One ; 15(3): e0223629, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32196505

RESUMO

Bats are well known reservoir hosts for RNA and DNA viruses. The use of captive bats in research has intensified over the past decade as researchers aim to examine the virus-reservoir host interface. In this study, we investigated the effects of captivity on the fecal bacterial microbiome of an insectivorous microbat, Mops condylurus, a species that roosts in close proximity to humans and has likely transmitted viral infections to humans. Using amplicon 16S rRNA gene sequencing, we characterized changes in fecal bacterial community composition for individual bats directly at the time of capture and again after six weeks in captivity. We found that microbial community richness by measure of the number of observed operational taxonomic units (OTUs) in bat feces increases in captivity. Importantly, we found the similarity of microbial community structures of fecal microbiomes between different bats to converge during captivity. We propose a six week-acclimatization period prior to carrying out infection studies or other research influenced by the microbiome composition, which may be advantageous to reduce variation in microbiome composition and minimize biological variation inherent to in vivo experimental studies.


Assuntos
Quirópteros/microbiologia , Microbioma Gastrointestinal/genética , Insetívoros/microbiologia , Animais , DNA Bacteriano/genética , Fezes/microbiologia , Firmicutes/genética , Insetos/microbiologia , Filogenia , Proteobactérias/genética , RNA Ribossômico 16S/genética , Análise de Sequência de RNA
11.
PLoS Negl Trop Dis ; 14(1): e0007952, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31961874

RESUMO

The significance of the integral membrane protein Niemann-Pick C1 (NPC1) in the ebolavirus entry process has been determined using various cell lines derived from humans, non-human primates and fruit bats. Fruit bats have long been purported as the potential reservoir host for ebolaviruses, however several studies provide evidence that Mops condylurus, an insectivorous microbat, is also an ebolavirus reservoir. NPC1 receptor expression in the context of ebolavirus replication in microbat cells remains unstudied. In order to study Ebola virus (EBOV) cellular entry and replication in M. condylurus, we derived primary and immortalized cell cultures from 12 different organs. The NPC1 receptor expression was characterized by confocal microscopy and flow cytometry comparing the expression levels of M. condylurus primary and immortalized cells, HeLa cells, human embryonic kidney cells and cells from a European microbat species. EBOV replication kinetics was studied for four representative cell cultures using qRT-PCR. The aim was to elucidate the suitability of primary and immortalized cells from different tissues for studying NPC1 receptor expression levels and their potential influence on EBOV replication. The NPC1 receptor expression level in M. condylurus primary cells differed depending on the organ they were derived from and was for most cell types significantly lower than in human cell lines. Immortalized cells showed for most cell types higher expression levels than their corresponding primary cells. Concluding from our infection experiments with EBOV we suggest a potential correlation between NPC1 receptor expression level and virus replication rate in vitro.


Assuntos
Quirópteros/genética , Reservatórios de Doenças/virologia , Ebolavirus/fisiologia , Proteína C1 de Niemann-Pick/genética , Proteína C1 de Niemann-Pick/metabolismo , Receptores Virais/genética , Animais , Quirópteros/metabolismo , Quirópteros/virologia , Humanos , Receptores Virais/metabolismo , Internalização do Vírus
12.
Virus Genes ; 56(1): 95-98, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31654295

RESUMO

To date, only two rodent-borne hantaviruses have been detected in sub-Saharan Africa. Here, we report the detection of a yet unknown hantavirus in a Natal mastomys (Mastomys natalensis) in Méliandou, Guinea, in 2014. The phylogenetic placement of this virus suggests that it might represent a cross-order spillover event from an unknown bat or eulipotyphlan host.


Assuntos
Infecções por Hantavirus/veterinária , Hantavirus/isolamento & purificação , Murinae/virologia , Doenças dos Roedores/virologia , Animais , Guiné , Hantavirus/classificação , Hantavirus/genética , Infecções por Hantavirus/virologia , Filogenia
13.
Front Immunol ; 10: 2414, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681302

RESUMO

Ebola virus infection of human dendritic cells (DCs) induces atypical adaptive immune responses and thereby exacerbates Ebola virus disease (EVD). Human DCs, infected with Ebola virus aberrantly express low levels of the DC activation markers CD80, CD86, and MHC class II. The T cell responses ensuing are commonly anergic rather than protective against EVD. We hypothesize that DCs derived from potential reservoir hosts such as bats, which do not develop disease signs in response to Ebola virus infection, would exhibit features associated with activation. In this study, we have examined Zaire ebolavirus (EBOV) infection of DCs derived from the Angolan free-tailed bat species, Mops condylurus. This species was previously identified as permissive to EBOV infection in vivo, in the absence of disease signs. M. condylurus has also been recently implicated as the reservoir host for Bombali ebolavirus, a virus species that is closely related to EBOV. Due to the absence of pre-existing M. condylurus species-specific reagents, we characterized its de novo assembled transcriptome and defined its phylogenetic similarity to other mammals, which enabled the identification of cross-reactive reagents for M. condylurus bone marrow-derived DC (bat-BMDC) differentiation and immune cell phenotyping. Our results reveal that bat-BMDCs are susceptible to EBOV infection as determined by detection of EBOV specific viral RNA (vRNA). vRNA increased significantly 72 h after EBOV-infection and was detected in both cells and in culture supernatants. Bat-BMDC infection was further confirmed by the observation of GFP expression in DC cultures infected with a recombinant GFP-EBOV. Bat-BMDCs upregulated CD80 and chemokine ligand 3 (CCL3) transcripts in response to EBOV infection, which positively correlated with the expression levels of EBOV vRNA. In contrast to the aberrant responses to EBOV infection that are typical for human-DC, our findings from bat-BMDCs provide evidence for an immunological basis of asymptomatic EBOV infection outcomes.


Assuntos
Quirópteros/imunologia , Quirópteros/virologia , Células Dendríticas/imunologia , Reservatórios de Doenças , Ebolavirus , Filoviridae , Animais , Biomarcadores , Quirópteros/genética , Citocinas/metabolismo , Células Dendríticas/metabolismo , Perfilação da Expressão Gênica , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Imunofenotipagem , Baço/imunologia , Baço/metabolismo , Transcriptoma
14.
Nat Commun ; 10(1): 5310, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31757953

RESUMO

The role of Africa in the dynamics of the global spread of a zoonotic and economically-important virus, such as the highly pathogenic avian influenza (HPAI) H5Nx of the Gs/GD lineage, remains unexplored. Here we characterise the spatiotemporal patterns of virus diffusion during three HPAI H5Nx intercontinental epidemic waves and demonstrate that Africa mainly acted as an ecological sink of the HPAI H5Nx viruses. A joint analysis of host dynamics and continuous spatial diffusion indicates that poultry trade as well as wild bird migrations have contributed to the virus spreading into Africa, with West Africa acting as a crucial hotspot for virus introduction and dissemination into the continent. We demonstrate varying paths of avian influenza incursions into Africa as well as virus spread within Africa over time, which reveal that virus expansion is a complex phenomenon, shaped by an intricate interplay between avian host ecology, virus characteristics and environmental variables.


Assuntos
Influenza Aviária/transmissão , Influenza Humana/transmissão , Doenças das Aves Domésticas/transmissão , África , África Ocidental , Animais , Humanos , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H5N8/genética , Vírus da Influenza A/genética , Influenza Aviária/economia , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Influenza Humana/economia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/economia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia
16.
Viruses ; 11(10)2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658738

RESUMO

As the phylogenetic organization of mammalian polyomaviruses is complex and currently incompletely resolved, we aimed at a deeper insight into their evolution by identifying polyomaviruses in host orders and families that have either rarely or not been studied. Sixteen unknown and two known polyomaviruses were identified in animals that belong to 5 orders, 16 genera, and 16 species. From 11 novel polyomaviruses, full genomes could be determined. Splice sites were predicted for large and small T antigen (LTAg, STAg) coding sequences (CDS) and examined experimentally in transfected cell culture. In addition, splice sites of seven published polyomaviruses were analyzed. Based on these data, LTAg and STAg annotations were corrected for 10/86 and 74/86 published polyomaviruses, respectively. For 25 polyomaviruses, a spliced middle T CDS was observed or predicted. Splice sites that likely indicate expression of additional, alternative T antigens, were experimentally detected for six polyomaviruses. In contrast to all other mammalian polyomaviruses, three closely related cetartiodactyl polyomaviruses display two introns within their LTAg CDS. In addition, the VP2 of Glis glis (edible dormouse) polyomavirus 1 was observed to be encoded by a spliced transcript, a unique experimental finding within the Polyomaviridae family. Co-phylogenetic analyses based on LTAg CDS revealed a measurable signal of codivergence when considering all mammalian polyomaviruses, most likely driven by relatively recent codivergence events. Lineage duplication was the only other process whose influence on polyomavirus evolution was unambiguous. Finally, our analyses suggest that an update of the taxonomy of the family is required, including the creation of novel genera of mammalian and non-mammalian polyomaviruses.


Assuntos
Antígenos Virais de Tumores/genética , Mamíferos/virologia , Polyomavirus , Animais , Evolução Biológica , Classificação , Genes Virais , Genoma Viral , Humanos , Filogenia , Polyomavirus/classificação , Polyomavirus/genética , Polyomavirus/isolamento & purificação
17.
Viruses ; 11(3)2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893858

RESUMO

New technologies enable viral discovery in a diversity of hosts, providing insights into viral evolution. We used one such approach, the virome capture sequencing for vertebrate viruses (VirCapSeq-VERT) platform, on 21 samples originating from six dead Maxwell's duikers (Philantomba maxwellii) from Taï National Park, Côte d'Ivoire. We detected the presence of an orthohepadnavirus in one animal and characterized its 3128 bp genome. The highest viral copy numbers were detected in the spleen, followed by the lung, blood, and liver, with the lowest copy numbers in the kidney and heart; the virus was not detected in the jejunum. Viral copy numbers in the blood were in the range known from humans with active chronic infections leading to liver histolytic damage, suggesting this virus could be pathogenic in duikers, though many orthohepadnaviruses appear to be apathogenic in other hosts, precluding a formal test of this hypothesis. The virus was not detected in 29 other dead duiker samples from the Côte d'Ivoire and Central African Republic, suggesting either a spillover event or a low prevalence in these populations. Phylogenetic analysis placed the virus as a divergent member of the mammalian clade of orthohepadnaviruses, though its relationship to other orthohepadnaviruses remains uncertain. This represents the first orthohepadnavirus described in an artiodactyl. We have tentatively named this new member of the genus Orthohepadnavirus (family Hepadnaviridae), Taï Forest hepadnavirus. Further studies are needed to determine whether it, or some close relatives, are present in a broader range of artiodactyls, including livestock.


Assuntos
Antílopes/virologia , Orthohepadnavirus/classificação , Orthohepadnavirus/isolamento & purificação , Animais , Costa do Marfim , Variação Genética , Genoma Viral , Parques Recreativos , Filogenia
18.
Res Vet Sci ; 124: 118-122, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30878633

RESUMO

Peste des petits ruminants (PPR) is a major Transboundary animal disease (TADs) of sheep and goats in tropical regions caused by PPRV which can also infect cattle without any clinical signs but inducing seroconversion. However the epidemiological role of cattle in the maintenance and spread of the disease is not known. For the purposes of the present study, cattle were infected with a wild type candidate from each of the four lineages of PPRV and placed in separate boxes. Naive goats were then introduced into each specific box for the 30 days duration of the experiment. The results showed that no clinical signs of PPR were recorded in these infected cattle nor in the in-contact goats. The nasal and oral swabs remained negative. Serum from animals infected with three (3) of the wild type isolates of PPRV showed high percentage inhibition (PI % > 65%) in a cELISA. Only two animals out of three infected with the Nigeria 75/3 strain of lineage 2 (mild strain) had specific anti-PPR antibodies but with PI% values around the threshold of the test. Our findings suggest that cattle are dead-end hosts for PPRV and do not play an epidemiological role in the maintenance and spread of PPRV. In a PPR surveillance programme, cattle can serve as indicators of PPRV infection.


Assuntos
Doenças dos Bovinos/transmissão , Doenças das Cabras/transmissão , Peste dos Pequenos Ruminantes/transmissão , Vírus da Peste dos Pequenos Ruminantes/fisiologia , Animais , Bovinos , Doenças dos Bovinos/virologia , Doenças das Cabras/virologia , Cabras , Peste dos Pequenos Ruminantes/virologia
19.
J Infect Dis ; 220(10): 1599-1608, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30657940

RESUMO

Bats are considered a reservoir species for Ebola viruses, but nonhuman primates (NHPs) have represented a source of infection in several outbreaks in humans. Here we report serological screening of blood or fecal samples from monkeys (n = 2322) and apes (n = 2327). Thirty-six NHP species from Cameroon, Democratic Republic of the Congo, and Ivory Coast were tested with a sensitive and specific Luminex-based assay for immunoglobulin G antibodies to 4 Ebola virus species. Using the simultaneous presence of antibodies to nucleoproteins and glycoproteins to define positivity, we showed that specific Ebola virus antibodies are not widespread among NHPs. Only 1 mustached monkey (Cercopithecus cephus) from Cameroon was positive for Sudan ebolavirus. These observations support that NHPs are most likely intermediate hosts for Ebola viruses. With the increasing frequency of Ebola outbreaks, it is crucial to identify the animal reservoir and understand the ecology of Ebola viruses to inform disease control.


Assuntos
Anticorpos Antivirais/sangue , Doenças dos Símios Antropoides/epidemiologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/veterinária , Imunoglobulina G/sangue , Doenças dos Macacos/epidemiologia , Animais , Doenças dos Símios Antropoides/imunologia , Camarões , Costa do Marfim , República Democrática do Congo , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/imunologia , Hominidae , Doenças dos Macacos/imunologia , Primatas , Estudos Soroepidemiológicos
20.
Transbound Emerg Dis ; 66(2): 882-896, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30548809

RESUMO

In July 2014, an outbreak of severe haemorrhagic disease in a domestic pig population, was reported in San-Pedro, the second seaport city of Ivory Coast. Animals of all age groups developed clinical signs consistent with African swine fever (ASF). Tissue and serum samples from dead pigs were sent to the laboratory for diagnostic confirmation and molecular characterization based on the partial B646L (p72), the full E183L (p54) gene and the central variable region of the B602L gene. The PCR results confirmed the outbreak of ASF. Phylogenetic analyses based on p72 and p54 sequences showed that the San-Pedro 2014 outbreak virus strain belongs to p72 genotype I. The Analysis of the tetrameric amino acid repeat regions of the B602L gene showed two repeat signatures which differ by an extra A = CAST in the second signature. The ASFV sequence of the San-Pedro 2014 outbreak strain is closely related to historical and recent ASFV strains collected in Angola and Cameroon whose ships have repeatedly visited the seaport of San-Pedro from March to June 2014. The 2014 viruses are distinct from the strains involved in the previous ASF wave in 1996 in Ivory Coast.


Assuntos
Vírus da Febre Suína Africana/genética , Febre Suína Africana/virologia , Surtos de Doenças/veterinária , Doenças dos Suínos/virologia , Febre Suína Africana/epidemiologia , Animais , Proteínas do Capsídeo/genética , Costa do Marfim/epidemiologia , Genoma Viral/genética , Genótipo , Técnicas de Genotipagem/veterinária , Filogenia , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/epidemiologia , Proteínas Virais/genética
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