Influenza A virus has one of sixteen possible Hemagglutinin (HA) surface proteins and one of nine possible Neuraminidase (NA) surface proteins. In early 2009, a novel H1N1 swine-origin influenza (S-OIV) A virus was identified in specimens obtained from patients in Mexico and the United States. The genetic make-up of this swine flu virus is unlike any other: it is an H1N1 strain that combines a triple assortment first identified in 1998 including human, swine, and avian influenza with two new pig H3N2 virus genes from Eurasia, themselves of recent human origin. This antibody is specific for the seasonal H1N1 influenza Hemagglutinin and will not recognize the corresponding Hemagglutinin sequence from the swine-origin H1N1 influenza (A/California/14/2009 (H1N1)).