Mameli Chiara, Fabiano Valentina, Daprai Laura, Bedogni Giorgio, Faccini Marino, Garlaschi Maria Laura, Penagini Francesca, Dilillo Dario, Torresani Erminio, Gramegna Maria, Zuccotti Gian Vincenzo
a Department of Pediatrics; Children's Hospital "V. Buzzi" ; University of Milan ; Milan , Italy.
Hum Vaccin Immunother. 2015;11(4):811-7. doi: 10.1080/21645515.2015.1010945.
Few epidemiological data are available after the introduction of the 13-valent pneumococcal vaccine (PCV13) in 2010. We performed repeat nasopharyngeal swabs and evaluated the serotype distribution of Streptococcus pneumoniae (SP) and its association with PCV13 vaccine status in healthy Italian children aged 3-59 months. SP serotypes were assessed by the Quellung reaction. 618 children appropriately (28%) or incompletely (72%) vaccinated for age with PCV13 were available at baseline (T0). 515 were re-evaluated at 6 months from baseline (T6) and 436 at 12 months from baseline (T12). The percentage of appropriately vaccinated subjects at T0, T6 and T12 was 28%, 67% and 92%, respectively. Random effects logistic regression models with robust 95% confidence intervals was used to estimate the time-related changes in SP and PCV13 carriage and marginal probabilities were obtained from such models. The age-corrected probability of SP carriage was 0.31 (95% CI 0.22 - 0.41) at T0, 0.32 (0.24 - 0.40) at T6 and 0.28 (0.20 - 0.35) at T12. The probability of PCV13 serotypes carriage was 0.025 (0.001 - 0.050) at T0, 0.018 (0.001 - 0.039) at T6 and 0.010 (0.001 - 0.023) at T12. A decrease in PCV13 serotypes and a shift in non-PCV13 serotypes colonization was observed. In particular, the 15A serotype accounted for 4%, 8% and 23% of SP isolates at T0, T6 and T12, respectively. In conclusion, the benefits of the PCV13 vaccination on SP carriage increase with increasing coverage rates. The shift of SP isolates toward non-PCV13 serotypes needs to be studied further.
2010年引入13价肺炎球菌疫苗（PCV13）后，可用的流行病学数据很少。我们对3至59个月大的健康意大利儿童进行了重复鼻咽拭子检查，并评估了肺炎链球菌（SP）的血清型分布及其与PCV13疫苗接种状况的关联。通过荚膜肿胀反应评估SP血清型。基线时（T0）有618名年龄适当（28%）或不完全（72%）接种PCV13的儿童。515名儿童在基线后6个月（T6）进行了重新评估，436名儿童在基线后12个月（T12）进行了重新评估。T0、T6和T12时适当接种疫苗的受试者百分比分别为28%、67%和92%。使用具有稳健95%置信区间的随机效应逻辑回归模型来估计SP和PCV13携带的时间相关变化，并从这些模型中获得边际概率。T0时SP携带的年龄校正概率为0.31（95%CI 0.22 - 0.41），T6时为0.32（0.24 - 0.40），T12时为0.28（0.20 - 0.35）。PCV13血清型携带的概率在T0时为0.025（0.001 - 0.050），T6时为0.018（0.001 - 0.039），T12时为0.010（0.001 - 0.023）。观察到PCV13血清型减少，非PCV13血清型定植发生转变。特别是，15A血清型在T0、T6和T12时分别占SP分离株的4%、8%和23%。总之，PCV13疫苗接种对SP携带的益处随着覆盖率的增加而增加。SP分离株向非PCV13血清型的转变需要进一步研究。
