Postvaccine Genetic Structure ofStreptococcus pneumoniaeSerotype 19A from Children in the United States

Abstract

BackgroundThe introduction of the 7-valent conjugate pneumococcal vaccine (PCV7) in children may result in serotype replacement. We estimated the rate of increase of invasive pneumococcal disease (IPD) caused by serotype 19A in children <5 years old and determined the genetic composition of these isolates