Impact of conjugate pneumococcal vaccine on antibiotic resistance

The fact that vaccinating infants and young children reduced drug-resistant Streptococcus pneumoniae (DRSP) disease and the carriage of pediatric DRSP serotypes in adults serves as the most compelling and definitive proof that children are responsible in a large part for the transmission of DRSP in the community. In a study to find out the efficacy of the conjugate pneumococcal vaccine against pneumococcal invasive disease caused by DRSP, 19,922 infants received pneumococcal conjugate vaccine (PCV) 9 and 19,914 received a placebo. Another study conducted by the Centers for Disease Control and Prevention (CDC), used laboratory-based active surveillance in multiple representative areas in the United States (the Active Bacterial Core Surveillance) to measure invasive diseases caused by DRSP from 1996 through 2004. The study by Byington and coworkers suggests that invasive pneumococcal infections with nonvaccine serotypes that are nonsusceptible to penicillin are increasing. The changes in proportions of pathogens isolated in cases of severe and refractory AOM before (1992 to 1998) and after (2000 to 2003) the introduction of universal vaccination in rural Kentucky were documented. The proportion of S. pneumoniae isolates decreased from 160 of 336 (48%) to 26 of 83 (31%) and the proportion of H. influenzae isolates increased from 137 of 336 (41%) to 46 of 83 (56%). Since antibiotic use selects for and promotes antibiotic resistance among S. pneumoniae strains, an important question is whether the use of PCVs can reduce antibiotic use.