Definition: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 1 and neuraminidase 1. The H1N1 subtype was responsible for the Spanish flu pandemic of 1918.
infection: coordinate IM with INFLUENZA, HUMAN (IM) in humans, or INFLUENZA IN BIRDS (IM) in birds, or ORTHOMYXOVIRIDAE INFECTIONS (IM) in other animals
Other names Viruses, H1N1; Virus, H1N1; Swine Origin Influenza A H1N1 Virus; H1N1 Viruses; Swine-Origin Influenza A H1N1 Virus; H1N1 Virus