Swine influenza A virus subtypes circulating in Brazilian commercial pig herds from 2012 to 2019

Abstract

The swine influenza A virus (SIAV) subtypes/lineages H1N1pdm09, H3N2, H1N2, and H1N1 of seasonal human origin are widespread in Brazilian swine herds. A monovalent inactivated H1N1pdm09 vaccine was licensed in Brazil in 2014. However, there are concerns about its efficacy due to the limited vaccine cross-protection against heterologous viruses and the potential for exacerbated reactions against vaccine strains. Thus, monitoring SIAVs subtypes/lineages that are circulating in the Brazilian swine population is important, by applying a fast and efficient diagnostic test in herd field samples. A RT-PCR assay was developed, using primers specific for HA subtyping of Brazilian SIAV, and was used to evaluate the occurrence of subtypes from samples collected between 2012 and 2019. From 167 field samples positive for influenza A, 117 were subtyped by nested RT-PCR assay. A higher occurrence of H1N1pdm was observed from 2012 to 2015, H3N2 in 2017, and H1hu in 2017 to 2019. A hemagglutination inhibition test was performed in serum samples received from 2017 to 2019, confirming these data. The molecular data highlights the importance of H1hu and H3N2 detection since there are no vaccines available for the subtypes/lineages and raises an alert of H1hu for its potential to infect humans. Serological data suggest a cyclical profile of occurrence between the H3N2 and H1N1pdm over time. Monitoring SIAVs circulating in Brazilian swine herds is necessary, which provides the relevant information for field veterinarians to apply effective control measures on the properties. Supplementary Information The online version contains supplementary material available at 10.1007/s42770-021-00550-y.

Human-to-swine introductions and onward transmission of 2009 H1N1 pandemic influenza viruses in Brazil

“…Since 2009, our understanding of the global diversity and evolution of IAV in swine increased to address paucity in data and concerns about the risk of interaction among H1N1pdm09 and enzootic IAV in pigs, and ultimately on how these viruses impact human health ( Ninomiya et al, 2002 ; Smith et al, 2009 ; Anderson et al, 2013 ; Vincent et al, 2013 ; Nelson et al, 2014 ). The expansion of IAV surveillance allowed a better understanding of the genetic diversity of IAV in swine, revealing the impact of frequent introductions of human viruses on IAV evolution in swine ( Pereda et al, 2010 ; Vijaykrishna et al, 2010 ; Ducatez et al, 2011 ; Chen et al, 2013 ; Nelson et al, 2014 , 2015a , c , d ; Pippig et al, 2016 ; Fraiha et al, 2021 ).…”

“…Most of these introductions had sustained onward transmission in swine prior to 2009, followed by reassortment with H1N1pdm09 lineage viruses. These events contributed to significant increases in genomic diversity ( Nelson et al, 2015b ; Fraiha et al, 2021 ; Tochetto et al, 2023 ).…”

“…Serological and molecular studies demonstrated that H1N1pdm09 viruses are endemic with variable prevalence from year to year in swine in Brazil ( Ciacci-Zanella et al, 2015 ; Dias et al, 2015 ; Fraiha et al, 2021 ). However, little information has been gathered about the population dynamics of the H1N1pdm09 lineage in Brazil.…”

Influenza A virus circulation in pig nurseries in the state of Santa Catarina, Brazil

“…agropec. bras., Brasília, v.57, e02816, 2022 DOI: 10.1590/S1678-3921.pab2022.v57.02816 introduction in the country in 2009 (Schaefer et al, 2011;Rajão et al, 2013) until 2015(Ciacci-Zanella et al, 2015Rech et al, 2018;Haach et al, 2020;Fraiha et al, 2021). However, since 2015, IAV outbreaks caused by the H3N2 virus have been reported more frequently among Brazilian pig herds (Haach et al, 2020;Fraiha et al, 2021).…”

33rd Brazilian Society for Virology (SBV) 2022 Annual Meeting

“…Andreza Parreiras Gonçalves (Fiocruz, MG) * Evaluation of the systemic immune response of patients with yellow fever through a plaque reduction neutralization test (PRNT) using a wild yellow fever virus [38] Renan Julio Mourão Ramos (UFRJ, RJ) Activated macrophage controls CHIKV and MAYV skeletal muscle replication and preserves infected fiber structure in co-culture cell mode [39] Michael Edward Miller (UNICAMP, SP) Regulatory action of interferon-stimulated genes (ISGs) in oropouche virus infection [40] Carolina Mattoso Lopes de Azevedo (IFRJ, RJ) 3D model of the placental barrier for functionality studies during ZIKV infection [41] Adriana Luchs (Instituto Adolfo Lutz, SP) Coxsackievirus A6 causing a hand-foot-and-mouth outbreak in Paraíba state, northeastern Brazil, 2018 [42] Veterinary Virology Larissa Mayumi Bueno (USP, SP) Alpha-and beta-coronavirus diversity in Brazilian bats [43] Laura Morais Nascimento Silva * The new subgenotype VI.2.1.2.1 of Newcastle disease virus in pigeons from Brazil is distinct from African viruses [44] Forlan Fernandes de Jesus (IOC, Fiocruz) Inclusion body disease in boa constrictor from Rio Grande do Sul, Brazil: a case report [45] Erica Azevedo Costa (UFMG, MG) Use of an inactivated recombinant vaccine against H1N1 swine influenza virus: immunization trial in a murine model [46] Laís Santos Rizotto (USP, SP) Analysis of the evolutionary profile of RDRP and NSP3 proteins of porcine epidemic diarrhea virus (PEDV) from samples obtained from Tadarida brasiliensis urban bats [47] * Indicates the best presentations selected by scientific committee.…”