Molecular detection and typing of influenza viruses: Are we ready for an influenza pandemic?

BackgroundWe cannot predict when an influenza pandemic will occur or which variant of the virus will cause it. Little information is currently available on the ability of laboratories to detect and subtype influenza viruses including the avian influenza viruses.ObjectivesTo assess the ability of laboratories to detect and subtype influenza viruses.Study designIn 2006 QCMD distributed an External Quality Assessment panel for the molecular detection and haemagglutinin subtyping of influenza viruses to 87 laboratories in 34 countries Worldwide, which were given 6 weeks to return results. These data were analysed to assess laboratory performance.ResultsInfluenza virus positive panel samples were correctly identified by 35–98% of laboratories. The correct haemagglutinin subtype was reported by 32–87% of laboratories that detected the virus: incorrect subtyping results included the reporting of avian influenza viruses as human strains and vice versa. Twelve laboratories reported false positives with some avian influenza viruses reported.ConclusionsThese data suggest that improvements are needed in the molecular detection of influenza viruses and influenza virus A haemagglutinin subtyping. Only rapid and accurate identification of circulating pandemic influenza virus will ensure that the maximum time is available for intervention.