H2n1

H2n1 is a hypothetical influenza A virus subtype. Influenza A viruses are classified into subtypes based on two surface proteins: hemagglutinin (H) and neuraminidase (N). There are 18 known hemagglutinin subtypes (H1-H18) and 11 known neuraminidase subtypes (N1-N11). The designation H2n1 would refer to a virus possessing the H2 hemagglutinin protein and the N1 neuraminidase protein.

Currently, there is no documented naturally occurring influenza A virus with the H2n1 subtype. However, researchers study various combinations of hemagglutinin and neuraminidase proteins, including those not currently circulating in animal or human populations, to understand potential pandemic threats and to develop vaccines. The H2 subtype has previously circulated in humans, most notably as the cause of the 1957 Asian flu pandemic (H2N2). The N1 neuraminidase subtype is also known and found in various avian influenza strains.

The study of hypothetical or rarely seen influenza subtypes like H2n1 is part of a broader effort in virology and public health to anticipate and prepare for novel influenza strains that could emerge and cause widespread illness. This research involves genetic sequencing, laboratory experiments to assess infectivity and transmissibility, and the development of broad-spectrum antiviral medications and vaccines.