tetano
Editor, Senior Moderator
Viruses
. 2021 Dec 28;14(1):47.
doi: 10.3390/v14010047.
Genetic Variability among Swine Influenza Viruses in Italy: Data Analysis of the Period 2017-2020
Chiara Chiapponi[SUP] 1 2 [/SUP], Alice Prosperi[SUP] 1 [/SUP], Ana Moreno[SUP] 1 [/SUP], Laura Baioni[SUP] 1 [/SUP], Silvia Faccini[SUP] 1 [/SUP], Roberta Manfredi[SUP] 1 [/SUP], Irene Zanni[SUP] 1 [/SUP], Valentina Gabbi[SUP] 1 [/SUP], Irene Calanchi[SUP] 1 [/SUP], Alice Fusaro[SUP] 3 [/SUP], Maria Serena Beato[SUP] 3 [/SUP], Lara Cavicchio[SUP] 3 [/SUP], Camilla Torreggiani[SUP] 1 [/SUP], Giovanni Loris Alborali[SUP] 1 [/SUP], Andrea Luppi[SUP] 1 [/SUP]
Affiliations
Abstract
Swine play an important role in the ecology of influenza A viruses (IAVs), acting as mixing vessels. Swine (sw) IAVs of H1N1 (including H1N1pdm09), H3N2, and H1N2 subtypes are enzootic in pigs globally, with different geographic distributions. This study investigated the genetic diversity of swIAVs detected during passive surveillance of pig farms in Northern Italy between 2017 and 2020. A total of 672 samples, IAV-positive according to RT-PCR, were subtyped by multiplex RT-PCR. A selection of strains was fully sequenced. High genotypic diversity was detected among the H1N1 and H1N2 strains, while the H3N2 strains showed a stable genetic pattern. The hemagglutinin of the H1Nx swIAVs belonged to HA-1A, HA-1B, and HA-1C lineages. Increasing variability was found in HA-1C strains with the circulation of HA-1C.2, HA-1C.2.1 and HA-1C.2.2 sublineages. Amino acid deletions in the HA-1C receptor binding site were observed and antigenic drift was confirmed. HA-1B strains were mostly represented by the Δ146-147 Italian lineage HA-1B.1.2.2, in combination with the 1990s human-derived NA gene. One antigenic variant cluster in HA-1A strains was identified in 2020. SwIAV circulation in pigs must be monitored continuously since the IAVs' evolution could generate strains with zoonotic potential.
Keywords: antigenic characterization; genetic characterization; influenza A virus; subtyping; swine.
. 2021 Dec 28;14(1):47.
doi: 10.3390/v14010047.
Genetic Variability among Swine Influenza Viruses in Italy: Data Analysis of the Period 2017-2020
Chiara Chiapponi[SUP] 1 2 [/SUP], Alice Prosperi[SUP] 1 [/SUP], Ana Moreno[SUP] 1 [/SUP], Laura Baioni[SUP] 1 [/SUP], Silvia Faccini[SUP] 1 [/SUP], Roberta Manfredi[SUP] 1 [/SUP], Irene Zanni[SUP] 1 [/SUP], Valentina Gabbi[SUP] 1 [/SUP], Irene Calanchi[SUP] 1 [/SUP], Alice Fusaro[SUP] 3 [/SUP], Maria Serena Beato[SUP] 3 [/SUP], Lara Cavicchio[SUP] 3 [/SUP], Camilla Torreggiani[SUP] 1 [/SUP], Giovanni Loris Alborali[SUP] 1 [/SUP], Andrea Luppi[SUP] 1 [/SUP]
Affiliations
- PMID: 35062251
- DOI: 10.3390/v14010047
Abstract
Swine play an important role in the ecology of influenza A viruses (IAVs), acting as mixing vessels. Swine (sw) IAVs of H1N1 (including H1N1pdm09), H3N2, and H1N2 subtypes are enzootic in pigs globally, with different geographic distributions. This study investigated the genetic diversity of swIAVs detected during passive surveillance of pig farms in Northern Italy between 2017 and 2020. A total of 672 samples, IAV-positive according to RT-PCR, were subtyped by multiplex RT-PCR. A selection of strains was fully sequenced. High genotypic diversity was detected among the H1N1 and H1N2 strains, while the H3N2 strains showed a stable genetic pattern. The hemagglutinin of the H1Nx swIAVs belonged to HA-1A, HA-1B, and HA-1C lineages. Increasing variability was found in HA-1C strains with the circulation of HA-1C.2, HA-1C.2.1 and HA-1C.2.2 sublineages. Amino acid deletions in the HA-1C receptor binding site were observed and antigenic drift was confirmed. HA-1B strains were mostly represented by the Δ146-147 Italian lineage HA-1B.1.2.2, in combination with the 1990s human-derived NA gene. One antigenic variant cluster in HA-1A strains was identified in 2020. SwIAV circulation in pigs must be monitored continuously since the IAVs' evolution could generate strains with zoonotic potential.
Keywords: antigenic characterization; genetic characterization; influenza A virus; subtyping; swine.
