Leach Amanda J, Morris Peter S, McCallum Gabrielle B, Wilson Cate A, Stubbs Liz, Beissbarth Jemima, Jacups Susan, Hare Kim, Smith-Vaughan Heidi C
Menzies School of Health Research, John Mathews Building (Bldg58), Royal Darwin Hospital, Rocklands Drive, Tiwi, Northern Territory, Australia.
BMC Infect Dis. 2009 Aug 4;9:121. doi: 10.1186/1471-2334-9-121.
In Australia in June 2001, a unique pneumococcal vaccine schedule commenced for Indigenous infants; seven-valent pneumococcal conjugate vaccine (7PCV) given at 2, 4, and 6 months of age and 23-valent pneumococcal polysaccharide vaccine (23PPV) at 18 months of age. This study presents carriage serotypes following this schedule.
We conducted cross sectional surveys of pneumococcal carriage in Aboriginal children 0 to 6 years of age living in remote Aboriginal communities (RACs) in 2003 and 2005. Nasal secretions were collected and processed according to published methods.
902 children (mean age 25 months) living in 29 communities in 2003 and 818 children (mean age 35 months) in 17 communities in 2005 were enrolled. 87% children in 2003 and 96% in 2005 had received two or more doses of 7PCV. From 2003 to 2005, pneumococcal carriage was reduced from 82% to 76% and reductions were apparent in all age groups; 7PCV-type carriage was reduced from 11% to 8%, and 23PPV-non-7PCV-type carriage from 31% to 25% respectively. Thus non-23PPV-type carriage increased from 57% to 67%. All these changes were statistically significant, as were changes for some specific serotypes. Shifts could not be attributed to vaccination alone. The top 10 of 40 serotypes identified were (in descending order) 16F, 19A, 11A, 6C, 23B, 19F, 6A, 35B, 6B, 10A and 35B. Carriage of penicillin non-susceptible (MIC > or = 0.12 microg/mL) strains (15% overall) was detected in serotypes (descending order) 19A, 19F, 6B, 16F, 11A, 9V, 23B, and in 4 additional serotypes. Carriage of azithromycin resistant (MIC > or = 2 microg/mL) strains (5% overall), was detected in serotypes (descending order) 23B, 17F, 9N, 6B, 6A, 11A, 23F, and in 10 additional serotypes including 6C.
Pneumococcal carriage remains high (approximately80%) in this vaccinated population. Uptake of both pneumococcal vaccines increased, and carriage was reduced between 2003 and 2005. Predominant serotypes in combined years were 16F, 19A, 11A, 6C and 23B. Antimicrobial non-susceptibility was detected in these and 17 additional serotypes. Shifts in serotype-specific carriage suggest a need more research to clarify the association between pneumococcal vaccination and carriage at the serotype level.
2001年6月在澳大利亚，针对原住民婴儿开始实施一种独特的肺炎球菌疫苗接种程序；在2、4和6月龄时接种七价肺炎球菌结合疫苗（7PCV），在18月龄时接种23价肺炎球菌多糖疫苗（23PPV）。本研究呈现了按照该程序接种后的携带血清型情况。
我们于2003年和2005年对居住在偏远原住民社区（RACs）的0至6岁原住民儿童的肺炎球菌携带情况进行了横断面调查。按照已发表的方法收集和处理鼻分泌物。
2003年在29个社区纳入了902名儿童（平均年龄25个月），2005年在17个社区纳入了818名儿童（平均年龄35个月）。2003年87%的儿童和2005年96%的儿童接种了两剂或更多剂次的7PCV。从2003年到2005年，肺炎球菌携带率从82%降至76%，且在所有年龄组中均有明显下降；7PCV血清型携带率从11%降至8%，23PPV非7PCV血清型携带率从31%降至25%。因此，非23PPV血清型携带率从57%升至67%。所有这些变化均具有统计学意义，一些特定血清型的变化也是如此。血清型的转变不能仅归因于疫苗接种。在鉴定出的40种血清型中，排名前十的（按降序排列）为16F、19A、11A、6C、23B、19F、6A、35B、6B、10A和35B。在血清型（按降序排列）19A、19F、6B、16F、11A、9V、23B以及另外4种血清型中检测到对青霉素不敏感（最低抑菌浓度[MIC]≥0.12μg/mL）菌株的携带（总体为15%）。在血清型（按降序排列）23B、17F、9N、6B、6A、11A、23F以及另外10种包括6C的血清型中检测到对阿奇霉素耐药（MIC≥2μg/mL）菌株的携带（总体为5%）。
在这个接种疫苗的人群中，肺炎球菌携带率仍然很高（约80%）。两种肺炎球菌疫苗的接种率均有所提高，且在2003年至2005年期间携带率有所下降。合并年份中的主要血清型为16F、19A、11A、6C和23B。在这些血清型以及另外17种血清型中检测到了抗菌药物不敏感性。血清型特异性携带情况的转变表明需要更多研究来阐明肺炎球菌疫苗接种与血清型水平携带之间的关联。
