Retrospective serological survey of influenza viruses in backyard pigs from Mexico City

Abstract

BackgroundIn the present study, we analyzed the presence of antibodies to four different influenza viruses (pH1N1, hH1N1, swH1N1, and swH3N2) in the sera of 2094 backyard pigs from Mexico City. The sera were obtained between 2000 and 2009.ObjectivesThe aim of this study was to perform a retrospective analysis of the 2000–2009 period to determine the seroprevalence of antibodies against pH1N1, hH1N1, swH1N1, and swH3N2 viruses in sera obtained from backyard pigs in Mexico City.MethodsAntibody detection was conducted with hemagglutination inhibition assay (HI) using four influenza viruses. We used linear regression to analyze the tendency of antibody serum titers throughout the aforementioned span.ResultsWe observed that the antibody titers for the pH1N1, swH1N1, and swH3N2 viruses tended to diminish over the study period, whereas the antibodies to hH1N1 remained at low prevalence for the duration of the years analyzed in this study. A non‐significant correlation (P > 0·05) between antibody titers for pH1N1 and swH1N1 viruses was observed (0·04). It contrasts with the significance of the correlation (0·43) observed between the swH1N1 and swH3N2 viruses (P < 0·01).ConclusionsOur findings showed no cross‐antigenicity in the antibody response against the same subtype. Antibodies against pH1N1 virus were observed throughout the 10‐year study span, implying that annual strains shared some common features with the pH1N1 virus since 2000, which would then be capable of supporting the ongoing presence of these antibodies.

Origin, distribution, and potential risk factors associated with influenza A virus in swine in two production systems in Guatemala

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Complete genome sequence of a novel influenza A H1N2 virus circulating in swine from Central Bajio region, Mexico

“…When two subtypes were present in a same sample, the one with highest titres showed higher specificity (Gaitán‐Peredo, ; Saavedra‐Montañez et al., ). Table shows the titres of specific antibodies against H1N1 swIAV detected in all farms determined as only positive for H1N2, to assess the specificity of positive results.…”

A Systematic Review Analyzing the Prevalence and Circulation of Influenza Viruses in Swine Population Worldwide

“…A retrospective study identified antibodies against swine-like H1N1, A(H1N1)pdm09, H3N2, and human-like H1N1 viruses in backyard swine in Mexico between 2000 to 2009. This investigation retrospectively determined that the classical-swine H1N1 virus was most widely present in Mexican swine before the 2009 influenza pandemic [305]. Further, a significant number of swine experiencing respiratory illness had H1N1 or H3N2 virus antibodies in commercial piggeries in Sonora Province of Mexico during October 2008-March 2009.…”