Loughlin Anita M, Hsu Katherine, Silverio Amy L, Marchant Colin D, Pelton Stephen I
From the Boston University School of Medicine and Boston Medical Center, Boston, MA.
Pediatr Infect Dis J. 2014 May;33(5):504-10. doi: 10.1097/INF.0000000000000279.
The direct impact of 13-valent pneumococcal conjugate vaccine (PCV13) on colonization with unique PCV13 serotypes and the uptake of vaccine necessary to create indirect protection in nonimmunized children were assessed.
Carriage surveillance among children <60 months began in July 2010 at a pediatric practice in Boston, MA. Children had nasopharyngeal cultures and parents completed questionnaires detailing demographics and health status. Concurrently, we monitored uptake of PCV13 in children in the community. Children were classified as "presumed immune" or "presumed nonimmune" based on age and PCV13 immunizations received. We assessed trends using adjusted prevalence rates calculated within rolling, 25-week, consecutive intervals.
Between July 2010 and June 2012, 1050 S. pneumoniae isolates were recovered from 1042 children. Eighty-nine isolates (8.5%) were 1 of 6 unique PCV13 serotypes. The expected fall/winter peak in PCV13 carriage was observed in nonimmune children, but was blunted in immune children. There was a 74% reduction in PCV13 colonization in immune compared with nonimmune children. We document a 50% or more decline in the PCV13 carriage in nonimmune children, at the time when the approximately 75% or more of the community children had received PCV13 and were considered immune. During the study, the difference in PCV13 serotype colonization prevalence in nonimmune and immune children disappeared. No evidence of replacement has been observed to date.
The direct impact of PCV13 on colonization was demonstrated. Evidence of indirect protection in unimmunized (nonimmune) children was observed as vaccine uptake reached 75% in the target community.
评估了13价肺炎球菌结合疫苗（PCV13）对携带特定PCV13血清型的直接影响，以及在未免疫儿童中产生间接保护所需的疫苗接种率。
2010年7月开始在马萨诸塞州波士顿的一家儿科诊所对60个月以下儿童进行携带情况监测。对儿童进行鼻咽培养，家长填写详细的人口统计学和健康状况问卷。同时，我们监测了社区儿童中PCV13的接种情况。根据年龄和接种的PCV13疫苗，将儿童分为“假定免疫”或“假定未免疫”。我们使用在连续25周的滚动间隔内计算的调整患病率来评估趋势。
2010年7月至2012年6月期间，从1042名儿童中分离出1050株肺炎链球菌。89株分离株（8.5%）属于6种特定PCV13血清型之一。在未免疫儿童中观察到了预期的PCV13携带秋冬高峰，但在免疫儿童中有所减弱。与未免疫儿童相比，免疫儿童的PCV13定植减少了74%。我们记录到，当社区中约75%或更多儿童接种了PCV13并被视为免疫时，未免疫儿童的PCV13携带率下降了50%或更多。在研究期间，未免疫和免疫儿童中PCV13血清型定植患病率的差异消失了。迄今为止，未观察到替代现象的证据。
证明了PCV13对定植的直接影响。当目标社区的疫苗接种率达到75%时，观察到了未免疫（未接种）儿童获得间接保护的证据。
