RESUMO
INTRODUCTION: Human metapneumovirus (hMPV) is an emergent human respiratory pathogen. This study aimed to evaluate the performance of direct immunofluorescence (DIF) to detect hMPV in a clinical laboratory setting. METHODS: Nasopharyngeal aspirate samples (448) of children and adults with respiratory illness were used to detect hMPV by using DIF and real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assays. RESULTS: In all, 36 (8%) samples were positive by DIF and 94 (21%) were positive by qRT-PCR. Direct immunofluorescence specificity was 99% and sensitivity was 38%. CONCLUSIONS: DIF is not very sensitive under clinical laboratory settings.
Assuntos
Técnica Direta de Fluorescência para Anticorpo , Metapneumovirus/isolamento & purificação , Infecções por Paramyxoviridae/diagnóstico , Infecções Respiratórias/diagnóstico , Adulto , Criança , Humanos , Metapneumovirus/genética , Metapneumovirus/imunologia , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/virologia , Sensibilidade e EspecificidadeRESUMO
Introduction: Human metapneumovirus (hMPV) is an emergent human respiratory pathogen. This study aimed to evaluate the performance of direct immunofl uorescence (DIF) to detect hMPV in a clinical laboratory setting. Methods: Nasopharyngeal aspirate samples (448) of children and adults with respiratory illness were used to detect hMPV by using DIF and real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assays. Results: In all, 36 (8%) samples were positive by DIF and 94 (21%) were positive by qRT-PCR. Direct immunofl uorescence specifi city was 99% and sensitivity was 38%. Conclusions: DIF is not very sensitive under clinical laboratory settings. (AU)
Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Doenças Respiratórias , Infecções Respiratórias/virologia , Virologia/instrumentação , Metapneumovirus/patogenicidade , Infecções por Paramyxoviridae , Influenza HumanaRESUMO
BACKGROUND: According to official records, dengue was introduced in Brazil in the 80's; since then several epidemics have occurred. Meanwhile, in Rio Grande do Sul (RS, Southern Brazil) the first autochthonous case occurred only in 2007. METHODOLOGY AND PRINCIPAL FINDINGS: In this study we report laboratory surveillance of dengue cases and seasonality of positive cases, describe serotypes and characterize the epidemiological pattern of dengue in RS from 2007 to 2013. A total of 9,779 serum samples from patients with suspected dengue fever were collected and submitted to molecular and/or serological analyses for dengue virus identification and serotyping, based on viral isolation, NS1 antigen detection and qRT-PCR, or Dengue IgM capture ELISA and MAC-ELISA. The first autochthonous dengue case in RS was confirmed in 2007 (DENV-3). While in 2008 and 2009 only imported cases were registered, autochthonous infection waves have been occurring since 2010. The highest number of dengue infections occurred in 2010, with DENV-1 and DENV-2 outbreaks in Northwestern RS. In 2011, another DENV-1 and DENV-2 outbreak occurred in the Northwestern region; moreover, DENV-4 was detected in travelers. In 2012, DENV-1 and DENV-4 co-circulated. DENV-2 circulation was only detected again in 2013, in high frequency (56.7%), co-circulating with DENV-4 (35%). Most infections occur in adults during summer. Differences in prevalence between genders were observed in 2007 (60% females), 2008 (60.8% males) and 2009 (77.5% males). CONCLUSIONS: According to results of dengue surveillance, there was an increase in the number of dengue cases in RS and of cities infested with Aedes aegypti, possibly as a consequence of introduction of new serotypes and the difficulty of health programs to control the vector.
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Vírus da Dengue , Dengue/epidemiologia , Dengue/virologia , Vigilância da População , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Dengue/história , Vírus da Dengue/classificação , Vírus da Dengue/genética , Surtos de Doenças , Feminino , História do Século XXI , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estações do Ano , Sorotipagem , Adulto JovemRESUMO
The neuraminidase (NA) genes of A(H1N1)pdm09 influenza virus isolates from 306 infected patients were analysed. The circulation of oseltamivir-resistant viruses in Brazil has not been reported previously. Clinical samples were collected in the state of Rio Grande do Sul (RS) from 2009-2011 and two NA inhibitor-resistant mutants were identified, one in 2009 (H275Y) and the other in 2011 (S247N). This study revealed a low prevalence of resistant viruses (0.8%) with no spread of the resistant mutants throughout RS.
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Antivirais/farmacologia , Farmacorresistência Viral/genética , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Mutação , Neuraminidase/genética , Oseltamivir/farmacologia , Brasil , Humanos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H1N1/genética , Testes de Sensibilidade Microbiana , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The neuraminidase (NA) genes of A(H1N1)pdm09 influenza virus isolates from 306 infected patients were analysed. The circulation of oseltamivir-resistant viruses in Brazil has not been reported previously. Clinical samples were collected in the state of Rio Grande do Sul (RS) from 2009-2011 and two NA inhibitor-resistant mutants were identified, one in 2009 (H275Y) and the other in 2011 (S247N). This study revealed a low prevalence of resistant viruses (0.8%) with no spread of the resistant mutants throughout RS.
