The changing profile of bacterial meningitis

From an NEJM study:

The incidence of meningitis changed by −31% (95% confidence interval [CI], −33 to −29) during the surveillance period, from 2.00 cases per 100,000 population (95% CI, 1.85 to 2.15) in 1998–1999 to 1.38 cases per 100,000 population (95% CI 1.27 to 1.50) in 2006–2007. The median age of patients increased from 30.3 years in 1998–1999 to 41.9 years in 2006–2007..

Of the 1670 cases reported during 2003–2007, S. pneumoniae was the predominant infective species (58.0%), followed by GBS (18.1%), N. meningitidis (13.9%), H. influenzae (6.7%), and L. monocytogenes (3.4%). An estimated 4100 cases and 500 deaths from bacterial meningitis occurred annually in the United States during 2003–2007.