One-step multiplex RT-qPCR for the detection and subtyping of influenza A virus in swine in Brazil.

This study describes the development and validation of a TaqMan based - one-step multiplex RT-qPCR to discriminate the hemagglutinin and neuraminidase genes of the three major IAV subtypes circulating in pigs in Brazil. The RT-qPCR assays presented 100% (95.7-100, CI 95%) of diagnostic sensitivity in the analysis of 85 IAVs, previously characterized by sequencing. The limits of detection ranged from 5.09 × 101 to 5.09 × 103 viral RNA copies/μL. For the analytical specificity, 73 pig samples collected during 2017 and 2018 were analyzed, resulting in the identification of the subtype in 74.0% (62.9-82.7, CI 95%) of samples. From these, 46.3% were H3N2, 33.3% were H1N1, 11.1% were H1N2 and 3.7% were HxN1. Mixed viral infections (3.7%) and reassortant viruses (1.9%) were also detected by the test. This multiplex RT-qPCR assay provides a fast and specific diagnostic tool for identification of different subtypes and lineages of IAV in pigs, contributing to the monitoring of influenza in swine. PMID: 30959063 [PubMed - as supplied by publisher]
Source: Journal of Virological Methods - Category: Virology Authors: Tags: J Virol Methods Source Type: research

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In this study, 15 H1N1, one H1N2, and four H3N2 strains were isolated from a total of 4080 nasal swabs which were collected from 20 pig farms in three provinces in China between 2016 and 2019. All the isolates were clustered into four genotypes. A new genotype represented by the H1N2 strain was found, whose fragments came from the triple reassortant H1N2 lineage, classical swine influenza virus (cs-H1N1) lineage, and 2009 H1N1 pandemic virus lineage. A/Sw/HB/HG394/2018(H1N1), which was clustered into the cs-H1N1 lineage, showed a close relationship with the 1918 pandemic virus. Mutations determining the host range specific...
Source: Viruses - Category: Virology Authors: Tags: Article Source Type: research
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Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
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Source: Current Infectious Disease Reports - Category: Infectious Diseases Source Type: research
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Source: Veterinary Research - Category: Veterinary Research Source Type: research
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Source: Preventive Veterinary Medicine - Category: Veterinary Research Source Type: research
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Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
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Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
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Source: Zoonoses and Public Health - Category: Infectious Diseases Authors: Tags: Original Article Source Type: research
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Source: Virus Genes - Category: Genetics & Stem Cells Source Type: research
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Source: Clinical and Vaccine Immunology - Category: Allergy & Immunology Authors: Tags: Clin Vaccine Immunol Source Type: research
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