Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Emerg Infect Dis ; 29(11): 2238-2245, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37877537

RESUMO

Marburg virus disease, caused by Marburg and Ravn orthomarburgviruses, emerges sporadically in sub-Saharan Africa and is often fatal in humans. The natural reservoir is the Egyptian rousette bat (ERB), which sheds virus in saliva, urine, and feces. Frugivorous ERBs discard test-bitten and partially eaten fruit, potentially leaving infectious virus behind that could be consumed by other susceptible animals or humans. Historically, 8 of 17 known Marburg virus disease outbreaks have been linked to human encroachment on ERB habitats, but no linkage exists for the other 9 outbreaks, raising the question of how bats and humans might intersect, leading to virus spillover. We used micro‒global positioning systems to identify nightly ERB foraging locations. ERBs from a known Marburg virus‒infected population traveled long distances to feed in cultivated fruit trees near homes. Our results show that ERB foraging behavior represents a Marburg virus spillover risk to humans and plausibly explains the origins of some past outbreaks.


Assuntos
Quirópteros , Doença do Vírus de Marburg , Marburgvirus , Animais , Humanos , Doença do Vírus de Marburg/epidemiologia , Sistemas de Informação Geográfica , Surtos de Doenças
2.
Parasit Vectors ; 16(1): 249, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488618

RESUMO

BACKGROUND: The human-pathogenic Kasokero virus (KASV) circulates in an enzootic transmission cycle between Egyptian rousette bats (ERBs; Rousettus aegyptiacus) and their argasid tick ectoparasites, Ornithodoros (Reticulinasus) faini. Although tick salivary gland components have been shown to potentiate virus infection in vertebrate non-reservoirs (i.e. incidental hosts or small animal models of disease), there is a lack of information on the effect of tick salivary gland components on viral infection and shedding in vertebrate reservoirs. METHODS: To determine the impact of tick salivary gland components on KASV infection and shedding in ERBs, KASV loads were quantified in blood, oral swab, rectal swab, and urine specimens collected daily through 18 days post inoculation from groups of ERBs intradermally inoculated with KASV or KASV + O. (R.) faini tick salivary gland extract (SGE). RESULTS: Bats inoculated with KASV + tick SGE had significantly lower peak and cumulative KASV viremias and rectal shedding loads compared to bats inoculated with KASV only. CONCLUSIONS: We report for the first time to our knowledge that tick salivary gland components dampen arbovirus infection and shedding in a vertebrate reservoir. This study advances our understanding of biological factors underlying arbovirus maintenance in nature.


Assuntos
Quirópteros , Marburgvirus , Ornithodoros , Animais , Humanos , Glândulas Salivares , Viremia
3.
Vet Pathol ; 60(3): 324-335, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36879492

RESUMO

Egyptian rousette bats (ERBs; Rousettus aegyptiacus; family Pteropodidae) are associated with a growing number of bunyaviruses of public health importance, including Kasokero virus (KASV), which was first identified as a zoonosis in Uganda in 1977. In this study, formalin-fixed paraffin-embedded tissues from a previous experiment in which KASV infection was confirmed in 18 experimentally infected ERBs were used for an in-depth analysis using histopathology, in situ hybridization (ISH) for detection of viral RNA, immunohistochemistry (IHC) to assess the mononuclear phagocyte system response, and quantitative digital image analysis to investigate virus clearance from the liver and spleen within a spatial context. Significant gross and histological lesions were limited to the liver, where KASV-infected bats developed mild to moderate, acute viral hepatitis, which was first observed at 3 days postinfection (DPI), peaked at 6 DPI, and was resolved by 20 DPI. A subset of bats had glycogen depletion (n = 10) and hepatic necrosis (n = 3), rarely with intralesional bacteria (n = 1). Virus replication was confirmed by ISH in the liver, spleen, lymph nodes, and tongue. In the liver, KASV replicated in the cytoplasm of hepatocytes, to a lesser extent in mononuclear phagocytes, and rarely in presumptive endothelial cells. Most KASV RNA, as detected by ISH, was cleared from the spleen and liver by 6 DPI. It is concluded that ERBs have effective mechanisms to respond to this virus, clearing it without evidence of clinical disease.


Assuntos
Quirópteros , Viroses , Animais , Reservatórios de Doenças , Células Endoteliais , Viroses/veterinária , Fígado/patologia , RNA Viral
4.
Sci Rep ; 12(1): 20936, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463252

RESUMO

The human-pathogenic Kasokero virus (KASV; genus Orthonairovirus) has been isolated from the sera of Egyptian rousette bats (ERBs; Rousettus aegyptiacus) captured in Uganda and unengorged Ornithodoros (Reticulinasus) faini ticks collected from the rock crevices of ERB colonies in South Africa and Uganda. Although evidence suggests that KASV is maintained in an enzootic transmission cycle between O. (R.) faini ticks and ERBs with potential for incidental virus spillover to humans through the bite of an infected tick, the vertebrate reservoir status of ERBs for KASV has never been experimentally evaluated. Furthermore, the potential for bat-to-bat and bat-to-human transmission of KASV is unknown. Herein, we inoculate two groups of ERBs with KASV; one group of bats is serially sampled to assess viremia, oral, fecal, and urinary shedding and the second group of bats is serially euthanized to assess virus-tissue tropism. Throughout the study, none of the bats exhibit overt signs of clinical disease. Following the detection of high KASV loads of long duration in blood, oral, fecal, and urine specimens collected from ERBs in the serial sampling group, all bats seroconvert to KASV. ERBs from the serial euthanasia group exhibit high KASV loads indicative of virus replication in the skin at the inoculation site, spleen, and inguinal lymph node tissue, and histopathology and in situ hybridization reveal virus replication in the liver and self-limiting, KASV-induced lymphohistiocytic hepatitis. The results of this study suggest that ERBs are competent, natural vertebrate reservoir hosts for KASV that can sustain viremias of appropriate magnitude and duration to support virus maintenance through bat-tick-bat transmission cycles. Viral shedding data suggests that KASV might also be transmitted bat-to-bat and highlights the potential for KASV spillover to humans through contact with infectious oral secretions, feces, or urine.


Assuntos
Quirópteros , Nairovirus , Ornithodoros , Humanos , Animais , Zoonoses , Fezes , Viremia
5.
N Engl J Med ; 386(24): 2283-2294, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35704480

RESUMO

BACKGROUND: In June 2019, the Bolivian Ministry of Health reported a cluster of cases of hemorrhagic fever that started in the municipality of Caranavi and expanded to La Paz. The cause of these cases was unknown. METHODS: We obtained samples for next-generation sequencing and virus isolation. Human and rodent specimens were tested by means of virus-specific real-time quantitative reverse-transcriptase-polymerase-chain-reaction assays, next-generation sequencing, and virus isolation. RESULTS: Nine cases of hemorrhagic fever were identified; four of the patients with this illness died. The etiologic agent was identified as Mammarenavirus Chapare mammarenavirus, or Chapare virus (CHAPV), which causes Chapare hemorrhagic fever (CHHF). Probable nosocomial transmission among health care workers was identified. Some patients with CHHF had neurologic manifestations, and those who survived had a prolonged recovery period. CHAPV RNA was detected in a variety of human body fluids (including blood; urine; nasopharyngeal, oropharyngeal, and bronchoalveolar-lavage fluid; conjunctiva; and semen) and in specimens obtained from captured small-eared pygmy rice rats (Oligoryzomys microtis). In survivors of CHHF, viral RNA was detected up to 170 days after symptom onset; CHAPV was isolated from a semen sample obtained 86 days after symptom onset. CONCLUSIONS: M. Chapare mammarenavirus was identified as the etiologic agent of CHHF. Both spillover from a zoonotic reservoir and possible person-to-person transmission were identified. This virus was detected in a rodent species, O. microtis. (Funded by the Bolivian Ministry of Health and others.).


Assuntos
Arenavirus do Novo Mundo , Febre Hemorrágica Americana , RNA Viral , Roedores , Animais , Arenavirus do Novo Mundo/genética , Arenavirus do Novo Mundo/isolamento & purificação , Bolívia/epidemiologia , Infecção Hospitalar/transmissão , Infecção Hospitalar/virologia , Transmissão de Doença Infecciosa , Febre Hemorrágica Americana/complicações , Febre Hemorrágica Americana/genética , Febre Hemorrágica Americana/transmissão , Febre Hemorrágica Americana/virologia , Febres Hemorrágicas Virais/genética , Febres Hemorrágicas Virais/transmissão , Febres Hemorrágicas Virais/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Reação em Cadeia da Polimerase , RNA Viral/genética , RNA Viral/isolamento & purificação , Ratos/virologia , Roedores/virologia , Zoonoses Virais/transmissão , Zoonoses Virais/virologia
6.
Emerg Infect Dis ; 27(2): 653-655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33496248

RESUMO

The epidemiology of Rift Valley fever virus (RVFV) and Crimean-Congo hemorrhagic fever virus (CCHFV) in Jordan is unknown. Our investigation showed 3% of 989 tested dairy cattle, sheep, and goats were RVFV seropositive and 14% were CCHFV seropositive. Ongoing surveillance is needed to assess risk to humans and protect public health.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia/epidemiologia , Febre do Vale de Rift/epidemiologia , Vírus da Febre do Vale do Rift , Animais , Anticorpos Antivirais , Bovinos , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/veterinária , Jordânia/epidemiologia , Vírus da Febre do Vale do Rift/imunologia , Ruminantes , Ovinos , Zoonoses
7.
Open Forum Infect Dis ; 6(10): ofz404, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31660366

RESUMO

Seoul orthohantavirus (SEOV) infections, uncommonly reported in the United States, often result in mild illness. We report a case of hemophagocytic lymphohistiocytosis secondary to SEOV infection that was domestically acquired in Washington, DC.

8.
Emerg Infect Dis ; 25(6): 1241-1243, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30844358
10.
Genome Announc ; 4(2)2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26966213

RESUMO

Draft genome sequences of Elizabethkingia meningoseptica and representatives of each of its four historically described genomospecies were sequenced here. Preliminary analysis suggests that Elizabethkingia miricola belongs to genomospecies 2, and both Elizabethkingia anophelis and Elizabethkingia endophytica are most similar to genomospecies 1.

11.
J Clin Microbiol ; 50(11): 3591-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22933599

RESUMO

Ninety-seven animal, human, and dairy Streptococcus porcinus or Streptococcus pseudoporcinus isolates in the CDC Streptococcus strain collection were evaluated on the basis of DNA-DNA reassociation, 16S rRNA and rpoB gene sequencing, conventional biochemical and Rapid ID 32 Strep identification methods, and antimicrobial susceptibility testing to determine their taxonomic status, characteristics for species differentiation, antimicrobial susceptibility, and relevance of clinical source. Nineteen of the 97 isolates (1 human, 18 swine) were identified as S. porcinus. The remaining 72 human isolates and 6 dairy isolates were identified as S. pseudoporcinus. The use of 16S rRNA or rpoB gene sequencing was required to differentiate S. porcinus from S. pseudoporcinus. The human and dairy S. pseudoporcinus isolates were biochemically distinct from each other as well as distinct by 16S rRNA and rpoB gene sequencing. Therefore, we propose the subspecies denominations S. pseudoporcinus subsp. hominis subsp. nov. for the human isolates and S. pseudoporcinus subsp. lactis subsp. nov. for the dairy isolates. Most strains were susceptible to the antimicrobials tested, with the exception of tetracycline. Two strains of each species were also resistant to clindamycin and erythromycin and carried the erm(A) (S. pseudoporcinus) or the erm(B) (S. porcinus) gene. S. porcinus was identified from a single human isolate recovered from a wound in an abattoir worker. S. pseudoporcinus was primarily isolated from the genitourinary tract of women but was also associated with blood, placental, and wound infections. Isolates reacting with group B antiserum and demonstrating wide beta-hemolysis should be suspected of being S. pseudoporcinus and not S. agalactiae.


Assuntos
Streptococcus/classificação , Animais , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Polimerases Dirigidas por DNA/genética , Laticínios/microbiologia , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/efeitos dos fármacos , Streptococcus/genética , Streptococcus/isolamento & purificação
12.
J Clin Microbiol ; 50(4): 1484-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22278841

RESUMO

Streptomyces cacaoi subsp. cacaoi, a Gram-positive, branching filamentous bacteria, was isolated from a scalp infection in a patient from Pondicherry, India. Phenotypic tests identified the isolate as a Streptomyces species, but 16S rRNA sequence analysis provided the species identification required for tracking of this emerging pathogen.


Assuntos
Dermatoses do Couro Cabeludo/diagnóstico , Streptomyces , Adulto , Feminino , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Diagnóstico Molecular , Dados de Sequência Molecular , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Dermatoses do Couro Cabeludo/microbiologia , Análise de Sequência de DNA , Streptomyces/efeitos dos fármacos , Streptomyces/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...