What is the naming logic behind the subtypes of influenza, H1N1 to H10N7, etc.? I only know the number gets larger with later discovery.

2fat	You could always look here. http://en.wikipedia.org/wiki/Influenzavirus_A Mar 20 07, 4:55 AM

skysmom65

Variants and subtypes Variants are identified and named according to the isolate that they are like and thus are presumed to share lineage (example Fujian flu virus like); according to their typical host (example Human flu virus); according to their subtype (example H3N2); and according to their deadliness (example LP). So a flu from a virus similar to the isolate A/Fujian/411/2002(H3N2) is called Fujian flu, human flu, and H3N2 flu. Variants are sometimes named according to the species (host) the strain is endemic in or adapted to. The main variants named using this convention are: Bird flu Human Flu Swine Flu Horse Flu Dog Flu Avian variants have also sometimes been named according to their deadliness in poultry, especially chickens: Low Pathogenic Avian Influenza (LPAI) Highly Pathogenic Avian Influenza (HPAI), also called: deadly flu or death flu The Influenza A virus subtypes are labeled according to an H number (for hemagglutinin) and an N number (for neuraminidase). Each subtype virus has mutated into a variety of strains with differing pathogenic profiles; some pathogenic to one species but not others, some pathogenic to multiple species. Most known strains are extinct strains. For example, the annual flu subtype H3N2 no longer contains the strain that caused the Hong Kong Flu. Influenza A viruses are negative sense, single-stranded, segmented RNA viruses. "There are 16 different HA antigens (H1 to H16) and nine different NA antigens (N1 to N9) for influenza A. Until recently, 15 HA types had been recognized, but a new type (H16) was isolated from black-headed gulls caught in Sweden and the Netherlands in 1999 and reported in the literature in 2005." [2] http://en.wikipedia.org/wiki/Influenzavirus_A#Variants_and_subtypes Mar 20 07, 7:45 AM