H5N9

English

Influenza nomenclature

Noun

H5N9 (uncountable)

1. (medicine) A strain of avian influenza.
   • 2025 January 27, Edward Helmore, “First outbreak of rare bird flu strain reported at California poultry farm”, in The Guardian‎^[1]:

     Authorities said the discovery of H5N9 bird flu in poultry came alongside the detection of the more common H5N1 strain on the same farm in Merced county, California, and that almost 119,000 birds on the farm had been killed since early December.