Decrease of Invasive Pneumococcal Infections in Children Among 8 Children’s Hospitals in the United States After the Introduction of the 7-Valent Pneumococcal Conjugate Vaccine

Abstract

Since the introduction of the PCV7, the number of invasive pneumococcal infections caused by vaccine-serogroup isolates among 8 US children's hospitals has decreased >75% among children < or =24 months old. In addition, penicillin resistance decreased in 2002 for the first time since our surveillance began in 1993-1994. However, we have noted that replacement may be developing with serogroups 15 and 33. Furthermore, penicillin resistance seems to be increasing among nonvaccine serogroups. Surveillance must be continued to detect the emergence of changes in the distribution of serotypes as well as antibiotic susceptibility.