In 2010, Burkina Faso completed the first nationwide mass-vaccination campaign of a meningococcal A conjugate vaccine, drastically reducing the incidence of disease caused by serogroup A meningococci. Since then, other strains, such as those belonging to serogroups W, X and C, have continued to cause outbreaks within the region. A carriage study was conducted in 2016 and 2017 in the country to characterize the meningococcal strains circulating among healthy individuals following the mass-vaccination campaign. Four cross-sectional carriage evaluation rounds were conducted in two districts of Burkina Faso, Kaya and Ouahigouya. Oropharyngeal swabs were collected for the detection of Neisseria meningitidis by culture. Confirmed N. meningitidis isolates underwent whole-genome sequencing for molecular characterization. Among 13 758 participants, 1035 (7.5 %) N . meningitidis isolates were recovered. Most isolates (934/1035; 90.2 %) were non-groupable and primarily belonged to clonal complex (CC) 192 (822/934; 88 %). Groupable isolates (101/1035; 9.8 %) primarily belonged to CCs associated with recent outbreaks in the region, such as CC11 (serogroup W) and CC10217 (serogroup C); carried serogroup A isolates were not detected. Phylogenetic analysis revealed several CC11 strains circulating within the country, several of which were closely related to invasive isolates. Three sequence types (STs) were identified among eleven CC10217 carriage isolates, two of which have caused recent outbreaks in the region (ST-10217 and ST-12446). Our results show the importance of carriage studies to track the outbreak-associated strains circulating within the population in order to inform future vaccination strategies and molecular surveillance programmes.

中文翻译：

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引入 A 群脑膜炎球菌结合疫苗 7 年后，对布基纳法索脑膜炎球菌携带分离株的分子见解


2010年，布基纳法索完成了首次全国范围内的A型脑膜炎球菌结合疫苗大规模接种活动，大幅降低了A群脑膜炎球菌引起的疾病发病率。此后，其他菌株，例如属于W、X和C血清群的菌株，继续在该地区引起疫情爆发。该国于 2016 年和 2017 年进行了一项携带研究，以表征大规模疫苗接种活动后健康个体中传播的脑膜炎球菌菌株。在布基纳法索的卡亚和瓦希古亚两个地区进行了四轮横断面运输评估。收集口咽拭子用于培养检测脑膜炎奈瑟菌。确认的脑膜炎奈瑟氏球菌分离株进行了全基因组测序以进行分子表征。在 13 758 名参与者中，有 1035 名 (7.5 %) N 。回收了脑膜炎分离株。大多数分离株（934/1035；90.2%）是不可分组的，主要属于克隆复合体（CC）192（822/934；88%）。可分组的分离株（101/1035；9.8%）主要属于与该地区近期爆发相关的CC，例如CC11（血清组W）和CC10217（血清组C）；未检测到携带 A 血清群的分离株。系统发育分析揭示了该国境内流行的几种 CC11 菌株，其中一些与入侵菌株密切相关。在 11 种 CC10217 携带菌株中鉴定出 3 种序列类型 (ST)，其中两种最近在该地区引起了疫情爆发（ST-10217 和 ST-12446）。 我们的结果表明，携带研究对于追踪人群中传播的疫情相关菌株的重要性，以便为未来的疫苗接种策略和分子监测计划提供信息。