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1.
Proc Natl Acad Sci U S A ; 110(40): 16151-6, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24043818

RESUMEN

The hepatitis B virus (HBV), family Hepadnaviridae, is one of most relevant human pathogens. HBV origins are enigmatic, and no zoonotic reservoirs are known. Here, we screened 3,080 specimens from 54 bat species representing 11 bat families for hepadnaviral DNA. Ten specimens (0.3%) from Panama and Gabon yielded unique hepadnaviruses in coancestral relation to HBV. Full genome sequencing allowed classification as three putative orthohepadnavirus species based on genome lengths (3,149-3,377 nt), presence of middle HBV surface and X-protein genes, and sequence distance criteria. Hepatic tropism in bats was shown by quantitative PCR and in situ hybridization. Infected livers showed histopathologic changes compatible with hepatitis. Human hepatocytes transfected with all three bat viruses cross-reacted with sera against the HBV core protein, concordant with the phylogenetic relatedness of these hepadnaviruses and HBV. One virus from Uroderma bilobatum, the tent-making bat, cross-reacted with monoclonal antibodies against the HBV antigenicity determining S domain. Up to 18.4% of bat sera contained antibodies against bat hepadnaviruses. Infectious clones were generated to study all three viruses in detail. Hepatitis D virus particles pseudotyped with surface proteins of U. bilobatum HBV, but neither of the other two viruses could infect primary human and Tupaia belangeri hepatocytes. Hepatocyte infection occurred through the human HBV receptor sodium taurocholate cotransporting polypeptide but could not be neutralized by sera from vaccinated humans. Antihepadnaviral treatment using an approved reverse transcriptase inhibitor blocked replication of all bat hepadnaviruses. Our data suggest that bats may have been ancestral sources of primate hepadnaviruses. The observed zoonotic potential might affect concepts aimed at eradicating HBV.


Asunto(s)
Quirópteros/virología , Hepadnaviridae/genética , Hepadnaviridae/patogenicidad , Zoonosis/virología , Animales , Secuencia de Bases , Línea Celular Tumoral , Reacciones Cruzadas/inmunología , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Genoma/genética , Virus de la Hepatitis B/genética , Hepatocitos/virología , Humanos , Immunoblotting , Hibridación in Situ , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Especificidad de la Especie , Tupaiidae
2.
J Gen Virol ; 94(Pt 9): 1984-1994, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23761408

RESUMEN

Bats host a broad diversity of coronaviruses (CoVs), including close relatives of human pathogens. There is only limited data on neotropical bat CoVs. We analysed faecal, blood and intestine specimens from 1562 bats sampled in Costa Rica, Panama, Ecuador and Brazil for CoVs by broad-range PCR. CoV RNA was detected in 50 bats representing nine different species, both frugivorous and insectivorous. These bat CoVs were unrelated to known human or animal pathogens, indicating an absence of recent zoonotic spill-over events. Based on RNA-dependent RNA polymerase (RdRp)-based grouping units (RGUs) as a surrogate for CoV species identification, the 50 viruses represented five different alphacoronavirus RGUs and two betacoronavirus RGUs. Closely related alphacoronaviruses were detected in Carollia perspicillata and C. brevicauda across a geographical distance exceeding 5600 km. Our study expands the knowledge on CoV diversity in neotropical bats and emphasizes the association of distinct CoVs and bat host genera.


Asunto(s)
Quirópteros/virología , Coronavirus/clasificación , Coronavirus/aislamiento & purificación , Variación Genética , Américas , Animales , Sangre/virología , Análisis por Conglomerados , Coronavirus/genética , Heces/virología , Intestinos/virología , Datos de Secuencia Molecular , Filogeografía , ARN Viral/genética , ARN Polimerasa Dependiente del ARN/genética , Análisis de Secuencia de ADN
3.
Braz J Microbiol ; 52(1): 107-124, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32990922

RESUMEN

We herein present a Brazilian guideline for the management of feline sporotrichosis, a mycosis caused by Sporothrix brasiliensis. This guideline is an effort of a national technical group organized by the Working Group on Sporothrix and Sporotrichosis of the International Society for Human and Animal Mycology (ISHAM). This publication intends to provide information on clinical-epidemiological aspects of this zoonosis, as well as a literature revision. Moreover, it gives some practical information on diagnosis and treatment of feline sporotrichosis. It also contains information that can be helpful for the prevention and control of S. brasiliensis transmission.


Asunto(s)
Antifúngicos/uso terapéutico , Enfermedades de los Gatos/tratamiento farmacológico , Sporothrix/efectos de los fármacos , Esporotricosis/veterinaria , Animales , Brasil , Enfermedades de los Gatos/microbiología , Gatos , Guías como Asunto , Sporothrix/genética , Sporothrix/fisiología , Esporotricosis/tratamiento farmacológico , Esporotricosis/microbiología
4.
J Wildl Dis ; 53(1): 144-147, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27705102

RESUMEN

Toxoplasma gondii and Neospora caninum are widespread cyst-forming coccidian parasites of the subfamily Toxoplasmatinae that infect a wide range of wild and domestic animals. Whereas T. gondii is a zoonotic disease, N. caninum is restricted to nonhuman animals. Some chiropteran species can be infected by T. gondii and present fatal toxoplasmosis. In most cases, T. gondii -infected bats are believed to remain asymptomatic and to act as an infection source to other animals. It is not known whether N. caninum can infect bats. We determined infection rates of T. gondii and N. caninum in free-living bats in the state of Bahia, Brazil. Brain samples from 97 bats of seven species, captured in 2008-15, were analyzed by PCRs for T. gondii and N. caninum . Two of the 97 samples were positive for T. gondii DNA. None of the samples were positive for N. caninum DNA, suggesting that the bats were not susceptible to N. caninum infection or that its prevalence was very low.


Asunto(s)
Anticuerpos Antiprotozoarios/análisis , Quirópteros/parasitología , Neospora/patogenicidad , Toxoplasma/patogenicidad , Toxoplasmosis Animal , Animales , Brasil , Coccidiosis , Neospora/aislamiento & purificación , Parásitos , Toxoplasma/aislamiento & purificación
5.
Nat Commun ; 3: 796, 2012 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-22531181

RESUMEN

The large virus family Paramyxoviridae includes some of the most significant human and livestock viruses, such as measles-, distemper-, mumps-, parainfluenza-, Newcastle disease-, respiratory syncytial virus and metapneumoviruses. Here we identify an estimated 66 new paramyxoviruses in a worldwide sample of 119 bat and rodent species (9,278 individuals). Major discoveries include evidence of an origin of Hendra- and Nipah virus in Africa, identification of a bat virus conspecific with the human mumps virus, detection of close relatives of respiratory syncytial virus, mouse pneumonia- and canine distemper virus in bats, as well as direct evidence of Sendai virus in rodents. Phylogenetic reconstruction of host associations suggests a predominance of host switches from bats to other mammals and birds. Hypothesis tests in a maximum likelihood framework permit the phylogenetic placement of bats as tentative hosts at ancestral nodes to both the major Paramyxoviridae subfamilies (Paramyxovirinae and Pneumovirinae). Future attempts to predict the emergence of novel paramyxoviruses in humans and livestock will have to rely fundamentally on these data.


Asunto(s)
Quirópteros/virología , Reservorios de Enfermedades/virología , Mamíferos/virología , Infecciones por Paramyxoviridae/virología , Paramyxoviridae/clasificación , Paramyxoviridae/aislamiento & purificación , Animales , Perros , Humanos , Ratones , Datos de Secuencia Molecular , Paramyxoviridae/genética , Filogenia
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