Norwegian Institute of Public Health, University of Oslo, Norway.
Clin Infect Dis. 2013 Feb;56(3):354-63. doi: 10.1093/cid/cis892. Epub 2012 Oct 19.
The conjugate vaccine against serogroup A Neisseria meningitidis (NmA), MenAfriVac, was first introduced in mass vaccination campaigns of 1-29-year-olds in Burkina Faso in 2010. It is not known whether MenAfriVac has an impact on NmA carriage.
We conducted a repeated cross-sectional meningococcal carriage study in a representative portion of the 1-29-year-old population in 3 districts in Burkina Faso before and up to 13 months after vaccination. One district was vaccinated in September 2010, and the other 2 were vaccinated in December 2010. We analyzed 25 521 oropharyngeal samples, of which 22 093 were obtained after vaccination.
In October-November 2010, NmA carriage prevalence in the unvaccinated districts was comparable to the baseline established in 2009, but absent in the vaccinated district. Serogroup X N. meningitidis (NmX) dominated in both vaccinated and unvaccinated districts. With 4 additional sampling campaigns performed throughout 2011 in the 3 districts, overall postvaccination meningococcal carriage prevalence was 6.95%, with NmX dominating but declining for each campaign (from 8.66% to 1.97%). Compared with a baseline NmA carriage prevalence of 0.39%, no NmA was identified after vaccination. Overall vaccination coverage in the population sampled was 89.7%, declining over time in 1-year-olds (from 87.1% to 26.5%), as unvaccinated infants reached 1 year of age. NmA carriage was eliminated in both the vaccinated and unvaccinated population from 3 weeks up to 13 months after mass vaccination (P = .003).
The disappearance of NmA carriage among both vaccinated and unvaccinated populations is consistent with a vaccine-induced herd immunity effect.
A 群脑膜炎奈瑟菌（NmA）结合疫苗（MenAfriVac）于 2010 年首次在布基纳法索对 1-29 岁人群进行大规模疫苗接种活动。目前尚不清楚 MenAfriVac 是否会对 NmA 携带产生影响。
我们在布基纳法索 3 个区的 1-29 岁人群中进行了一项脑膜炎奈瑟菌携带的重复横断面研究，这些区在疫苗接种前和接种后 13 个月内进行了监测。其中 1 个区于 2010 年 9 月接种，另外 2 个区于 2010 年 12 月接种。我们分析了 25521 份咽拭子样本，其中 22093 份样本是在接种后获得的。
2010 年 10 月至 11 月，未接种疫苗区的 NmA 携带率与 2009 年建立的基线水平相当，但接种疫苗区无 NmA 携带。血清群 X 脑膜炎奈瑟菌（NmX）在接种和未接种疫苗的地区均占主导地位。在 2011 年的 3 个区进行了 4 次额外的采样活动后，总的接种后脑膜炎奈瑟菌携带率为 6.95%，NmX 占主导地位，但每个活动都呈下降趋势（从 8.66%降至 1.97%）。与基线 NmA 携带率 0.39%相比，接种后未发现 NmA。抽样人群的总体疫苗接种率为 89.7%，1 岁以下人群的接种率随时间逐渐下降（从 87.1%降至 26.5%），因为未接种的婴儿达到 1 岁。大规模疫苗接种后 3 周至 13 个月，接种人群和未接种人群中 NmA 携带均被消除（P=0.003）。
接种人群和未接种人群 NmA 携带的消失与疫苗诱导的群体免疫效应一致。
