Preparing for the next influenza pandemic.

There are 3 requirements for an influenza virus to cause a pandemic. It must be antigenically novel, cause severe disease, and transmit easily from human to human. Highly pathogenic avian influenza viruses of the H5N1 subtype currently circulating in bird populations in Asia, Africa, and Europe have met 2 of these criteria, and there is significant concern that these viruses will be the cause of the next pandemic. International efforts to prepare for a possible pandemic are underway. Priorities for pandemic planning include surveillance of influenza viruses in wild bird populations and at the avian-human interface, research into factors affecting the pathogenicity of these strains, stockpiling effective antivirals for use as a stopgap until an appropriate vaccine can be developed and distributed, and gaining an improved understanding of the utility of nonpharmaceutical interventions to slow or prevent the spread of these viruses within humans. Although considerable progress has been made in recent years towards readying the world for such an event, there is more work to be done. Physicians and hospitals can begin by educating themselves on the problem and developing a pandemic plan for their own practice or organization.