Figure 1From: Virological and serological surveillance for type A influenza in the black-legged kittiwake (Rissa tridactyla)cELISA and HI assay. Results from the cELISA for detection of antibodies to influenza A virus NP in black-legged kittiwake sera collected in 2009. Sera from adults (n = 80) and three-week old chicks (n = 18) were tested. A result was defined as positive when the competition was ≤ 45%, doubtful at 45-50% and negative at ≥ 50% competition (a). The distribution of HI titres against AIV subtypes H16 (b) and H13 (c) in sera from black-legged kittiwakes (n = 48).Back to article page