The approach to diagnosis using real-time RT-PCR adopted in most laboratories has been
based on initial generic detection of influenza A virus in clinical specimens, primarily by initially
targeting the matrix (M) gene, which is highly conserved for all influenza A viruses, followed by
specific real-time RT-PCR testing for H5 and H7 subtype viruses. For subtype identification,
primers used in TaqMan real-time RT-PCRs are targeted at the HA2 region, as this is relatively
well conserved within the haemagglutinin genes of the H5 and H7 subtypes (Spackman et al.,