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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AbstractPurpose of ReviewZoonotic influenza viruses are those that cross the animal-human barrier and can cause disease in humans, manifesting from minor respiratory illnesses to multiorgan dysfunction. They have also been implicated in the causation of deadly pandemics in recent history. The increasing incidence of infections caused by these viruses worldwide has necessitated focused attention to improve both diagnostic as well as treatment modalities. In this first part of a two-part review, we describe the structure of zoonotic influenza viruses, the relationship between mutation and pandemic capacity, pathogenesis of i...
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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Source: Annals of Global Health - Category: Global & Universal 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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