Abstract Title
The Role of Turkes in Influenza A Cross-Species Transmission
Abstract
Swine are recognized as “mixing vessels”, as they can be simultaneously infected with avian, human, and swine-origin influenza viruses. However, the role of turkeys in the emergence of novel zoonotic influenza virus has been poorly investigated. North-eastern Italy, home to one of Europe’s highest concentrations of turkey farms, provides a unique setting to investigate such potential. This study reports three cases of cross-species transmission in three distinct turkey farms located in northern Italy.
In 2019, an H1N1pdm09 infection was diagnosed in a breeding turkey farm. Genome characterization showed that the virus was closely related to human viruses circulating during the 2018-2019, suggesting a human-to-turkey transmission, likely from farm workers. In 2020 a commercial turkey farm was found positive for a swine-origin avH1N1 (1C.2.1 clade, A genotype) strain and in 2024, a third case was reported in turkeys infected with another swine influenza H1N1 strain (clade 1.C.2.4, U genotype). The distinct infections observed in turkeys in 2020 and 2024 turned out to be genetically related to viruses detected in pig farms managed by the same company, indicating a likely swine-to-turkey transmission.
These incidents caused by pig- and human-origin influenza viruses underscore the potential of turkeys as intermediate hosts, facilitating cross-species influenza transmission and the emergence of novel reassorted strains. This study emphasises the need for systematic cross-species influenza surveillance and highlights the importance of surveillance in humans exposed to influenza virus-carrying animals in a One Health approach to pandemic preparedness.
In 2019, an H1N1pdm09 infection was diagnosed in a breeding turkey farm. Genome characterization showed that the virus was closely related to human viruses circulating during the 2018-2019, suggesting a human-to-turkey transmission, likely from farm workers. In 2020 a commercial turkey farm was found positive for a swine-origin avH1N1 (1C.2.1 clade, A genotype) strain and in 2024, a third case was reported in turkeys infected with another swine influenza H1N1 strain (clade 1.C.2.4, U genotype). The distinct infections observed in turkeys in 2020 and 2024 turned out to be genetically related to viruses detected in pig farms managed by the same company, indicating a likely swine-to-turkey transmission.
These incidents caused by pig- and human-origin influenza viruses underscore the potential of turkeys as intermediate hosts, facilitating cross-species influenza transmission and the emergence of novel reassorted strains. This study emphasises the need for systematic cross-species influenza surveillance and highlights the importance of surveillance in humans exposed to influenza virus-carrying animals in a One Health approach to pandemic preparedness.
Co-Author(s)
Cavicchio Lara¹, Zecchin Bianca¹, Tassoni Luca¹, Pastori Ambra¹, Giussani Edoardo¹, Salviato Annalisa¹, Fincato Alice¹, Beato Maria Serena¹*, Ceglie Letizia¹, Monne Isabella¹, Bortolami Alessio¹, Gobbo Federica¹, Terregino Calogero¹, Fusaro Alice¹.
¹Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell’università, 10, 35020 Legnaro (Padua), Italy
*currently: Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche “Togo Rosati” (IZSUM)
Abstract Category
Notable outbreaks, field and molecular epidemiology, and surveillance in poultry