The Norovirus ELISA is an in-vitro-diagnostic device for direct detection of Norovirus specific antigens in stool specimens.Norovirus antigens from stool specimens and the positive control react with polyclonal anti-Norovirus antibodies coated on the solid phase of the microplate. After incubation non-bound material is removed by a washing step. Subsequently bound antigens specifically react with horseradish peroxidase (HRP) labeled polyclonal anti-Norovirus antibodies during a second incubation period. Unbound conjugate is removed by a washing step. HRP converts the subsequently added colourless chromogenic substrate solution (TMB / H2O2) into a blue product. The enzyme reaction is terminated by sulphuric acid dispensed into the wells turning the solution from blue to yellow. The optical density (OD) of the solution read at 450 / ≥ 620 nm is directly proportional to the specifically bound amount of Norovirus antigens. By means of the calculated cut-off value, results are interpreted either as positive or negative.