Can you tell me more about the new avian influenza virus strains that have been recently identified in the Pacific flyway of the United States?
I see various numbers next to the “H” and the “N” in avian flu designations. What do those different numbers mean?
Avian influenza viruses are classified by a combination of two groups of proteins: hemagglutinin or “H” proteins, of which there are 16 (H1 to H16), and neuraminidase or “N” proteins, of which there are nine (N1 to N9).
The designation of low or highly pathogenic avian influenza refers to the potential for these viruses to kill chickens.