Background and Significance
Influenza, a viral infectious disease caused by influenza viruses, primarily affect the respiratory system and result in hospitalization and death among both the young and the elderly, as well as the pregnant women and chronically ill; epidemics cause an average of 25,000 deaths annually in the United States alone. (1). The human influenza virus has three types: Type A, type B, and type C. Influenza A has subtypes, classified by surface antigens, hemagglutinin (HA) and neuraminidase (NA). Influenza A has 16 different hemagglutinin subtypes and 9 different neuraminidase subtypes and strains have a nomenclature of H (1-16) N (1-9) ( ...