Recognizes H1N1 (A/California/04/2009) HA; H1N1 (A/California/07/2009) HA. Has cross-reactivity in ELISA with: H1N1 (A/Solomon Islands/3/2006) HA; H1N1 (A/Ohio/UR06-0091/2007) HA; H1N1 (A/New Caledonia/20/1999) HA; H1N1 (A/Puerto Rico/8/1934) HA; H1N1 (A