Evaluation of the subtype specificity of monoclonal antibodies raised against H1 and H3 subtypes of human influenza A virus hemagglutinins

Three previously described monoclonal antibodies (MAbs) specific for influenza A(H1) hemagglutinins (HA) revealed high sensitivity (98.2 to 99.1%) and specificity (100%) when tested against 245 strains of different subtypes. One of them was included in the World Health Organization's influenza reagent kit for 2001 to 2002. In contrast, two MAbs raised against human influenza A(H3) HA revealed cross-reactivity with viruses of other subtypes.