Influenza A viruses, including subtypes such as H1N1, H1N2, and H3N2, are commonly present in swine. Occasionally, these viruses infect humans, typically through direct or indirect exposure to pigs or contaminated environments, according to UKHSA officials.
The broader subtype, influenza A(H1N2)v, has been reported in 50 human cases worldwide, including Canada. In late 2021, Manitoba reported an isolated human case of variant H1N2 to the Public Health Agency of Canada, with no evidence of human-to-human transmission.
While the world witnessed the 2009 "swine flu" pandemic, triggered by a different strain, H1N1, the current case remains unrelated to that outbreak. H1N1 now circulates seasonally among humans and is distinct from the virus strains observed in swine populations.