The Influenza A+B One Step Assay is a rapid chromatographic immunoassay for the qualitative detection of Influenza type A (including subtype A (H1N1) and A (H3N2)) and type B antigens in human nasopharyngeal specimens to aid in the diagnosis of Influenza infection. Influenza is caused by a virus that attacks mainly the upper respiratory tract – the nose, throat and bronchi and rarely also the lungs. In some people, the infection may lead to severe complications of underlying diseases, pneumonia and death. The currently circulating influenza viruses that cause human disease are divided into group A and B. Influenza A has 2 subtypes which are important for humans: A (H3N2) and A (H1N1), of which the former is currently associated with most deaths.