Four years of lessons learned: The 2001-2004 Maryland influenza prevention seasons.

More than 36,000 Americans die and 200,000 more are hospitalized because of influenza every\year. Despite the wide availability of a vaccine to prevent influenza, the vast majority of Americans go unimmunized. The Maryland Department of Health and Mental Hygiene (DHMH) and the Maryland Partnership for Prevention (MPP) collect data about the state's local health departments' influenza season practices and experiences and compile them into the annual Maryland Influenza Season Final Report. The report becomes a tool for DHMH, MPP, and the state's 24 local health departments to plan improvements in influenza vaccination services. This article chronicles four influenza seasons. Influenza season challenges experienced in three of the last four influenza seasons underscore the importance of coordination and communication efforts to ensure that vaccine is efficiently delivered to the most vulnerable populations. The partnership between DHMH and MPP has facilitated access to information on ordering and administration practices, communication systems, community partnerships, and lessons learned, thus enabling the state of Maryland to continually optimize its influenza vaccination promotion efforts.