Agence de Médecine Préventive, Ouagadougou, Burkina Faso.
Institute of Global Health, University of Geneva, Geneva, Switzerland.
J Infect Dis. 2021 Sep 1;224(12 Suppl 2):S258-S266. doi: 10.1093/infdis/jiab037.
Burkina Faso, a country in Africa's meningitis belt, introduced 13-valent pneumococcal conjugate vaccine (PCV13) in October 2013, with 3 primary doses given at 8, 12 and 16 weeks of age. To assess whether the new PCV13 program controlled pneumococcal carriage, we evaluated overall and serotype-specific colonization among children and adults during the first 3 years after introduction.
We conducted 2 population-based, cross-sectional, age-stratified surveys in 2015 and 2017 in the city of Bobo-Dioulasso. We used standardized questionnaires to collect sociodemographic, epidemiologic, and vaccination data. Consenting eligible participants provided nasopharyngeal (all ages) and oropharyngeal (≥5 years only) swab specimens. Swab specimens were plated onto blood agar either directly (2015) or after broth enrichment (2017). Pneumococci were serotyped by conventional multiplex polymerase chain reaction. We assessed vaccine effect by comparing the proportion of vaccine-type (VT) carriage among colonized individuals from a published baseline survey (2008) with each post-PCV survey.
We recruited 992 (2015) and 1005 (2017) participants. Among children aged <5 years, 42.8% (2015) and 74.0% (2017) received ≥2 PCV13 doses. Among pneumococcal carriers aged <1 year, VT carriage declined from 55.8% in 2008 to 36.9% in 2017 (difference, 18.9%; 95% confidence interval, 1.9%-35.9%; P = .03); among carriers aged 1-4 years, VT carriage declined from 55.3% to 31.8% (difference, 23.5%; 6.8%-40.2%; P = .004); and among participants aged ≥5 years, no significant change was observed.
Within 3 years of PCV13 implementation in Burkina Faso, we documented substantial reductions in the percentage of pneumococcal carriers with a VT among children aged <5 years, but not among persons aged ≥5 years. More time, a change in the PCV13 schedule, or both, may be needed to better control pneumococcal carriage in this setting.
布基纳法索是非洲脑膜炎带的一个国家，于 2013 年 10 月引入 13 价肺炎球菌结合疫苗（PCV13），为 8、12 和 16 周龄的儿童接种 3 剂基础疫苗。为评估新的 PCV13 计划是否控制了肺炎球菌定植，我们在引入后的头 3 年评估了儿童和成人的总体及血清型特异性定植情况。
我们于 2015 年和 2017 年在波波迪乌拉索市进行了 2 项基于人群的、横断面、年龄分层调查。我们使用标准化问卷收集社会人口统计学、流行病学和疫苗接种数据。同意参与的合格参与者提供鼻咽（所有年龄）和口咽（≥5 岁）拭子标本。拭子标本直接（2015 年）或经肉汤富集后（2017 年）接种到血琼脂平板上。通过传统的多重聚合酶链反应对肺炎球菌进行血清分型。我们通过比较 2008 年发表的基线调查（2008 年）与每个 PCV 后调查中定植个体的疫苗型（VT）携带比例，评估疫苗效果。
我们招募了 992 名（2015 年）和 1005 名（2017 年）参与者。5 岁以下儿童中，42.8%（2015 年）和 74.0%（2017 年）接受了≥2 剂 PCV13。1 岁以下肺炎球菌携带者中，VT 携带率从 2008 年的 55.8%下降至 2017 年的 36.9%（差异，18.9%；95%置信区间，1.9%-35.9%；P =.03）；1-4 岁儿童中，VT 携带率从 55.3%下降至 31.8%（差异，23.5%；6.8%-40.2%；P =.004）；≥5 岁的参与者中未观察到显著变化。
在布基纳法索实施 PCV13 后的 3 年内，我们记录到 5 岁以下儿童中携带 VT 的肺炎球菌携带者比例大幅下降，但≥5 岁人群中未观察到这一情况。可能需要更多的时间、改变 PCV13 接种时间表或两者兼施，以更好地控制该地区的肺炎球菌定植。
