Animals (Jun 2022)

Influenza A in Wild Boars: Viral Circulation in the Emilia-Romagna Region (Northern Italy) between 2017 and 2022

  • Alice Prosperi,
  • Laura Soliani,
  • Elena Canelli,
  • Laura Baioni,
  • Valentina Gabbi,
  • Camilla Torreggiani,
  • Roberta Manfredi,
  • Irene Calanchi,
  • Giovanni Pupillo,
  • Filippo Barsi,
  • Patrizia Bassi,
  • Laura Fiorentini,
  • Matteo Frasnelli,
  • Maria Cristina Fontana,
  • Andrea Luppi,
  • Chiara Chiapponi

DOI
https://doi.org/10.3390/ani12121593
Journal volume & issue
Vol. 12, no. 12
p. 1593

Abstract

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A systematic surveillance against influenza A viruses (IAVs) in the Suidae population is essential, considering their role as IAV mixing vessels. However, the viral circulation in wild Sus scrofa species is poorly investigated in comparison to the knowledge of IAV infection dynamics in domestic pigs. This study investigated the circulation and the genetic diversity of wild boars’ IAVs detected in the Emilia-Romagna region (2017–2022). A total of 4605 lung samples were screened via an M gene real-time RT-PCR for SwIAV; positive samples were subtyped by multiplex RT-PCR, and viral isolation was attempted. Isolated strains (3 out of the 17 positives) were fully sequenced to evaluate viral genotypic diversity. H1N1 was the most frequently detected subtype, with identification of H1pdm09N1 and H1avN1. Whole-genome phylogenetic analysis revealed SwIAVs belonging to different genotypes, with different genetic combinations, and highlighted the simultaneous circulation of the same genotypes in both pigs and wild boars, supporting the hypothesis of SwIAV spillover events at the wildlife–livestock interface. This study represents an update on the wild boar SwIAV Italian situation, and the strains’ complete genome analysis showed an evolving and interesting situation that deserves further investigation.

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