Widely recognize Influenza A Nucleoprotein. Has cross-reactivity in ELISA with: H1N1 (A/Brevig Mission/1/1918) NP; H1N1 (A/Brisbane/02/2018) NP; H1N1 (A/California/07/2009) NP; H1N1 (A/Guangdong-Maonan/SWL1536/2019) NP; H1N1 (A/Hawaii/70/2019) NP; H1N1 (