The changing epidemiology of meningococcal disease in North America 1945-2010.

The epidemiology of Invasive Meningococcal Disease (IMD) is distinct in the United States and Canada compared with other countries. This review describes the incidence, mortality and vaccination strategies relevant to IMD in these countries over the past 65 y. The incidence of IMD has remained consistently low in both countries during this period. Serogroup B and serogroup C have been the most prominent disease-causing serogroups. Notably, serogroup Y has recently become an important cause of IMD in the USA, but has not been as prominent in Canada. Periodic rises in incidence have been characterized by local outbreaks that have raised public concern, especially those caused by serogroup C in Canada, and serogroup B in the USA. Case fatality rates have remained consistent at around 10-20%, but vary by age and serogroup. Recent outbreaks have led to the introduction of vaccination programs for both outbreak control and routine immunization.