Vaccinology and Immunology Research Trials Unit, Women's and Children's Health Network, Adelaide, South Australia, Australia.
Robinson Research Institute and Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.
Clin Infect Dis. 2021 Jul 1;73(1):e99-e106. doi: 10.1093/cid/ciaa610.
Higher density of Neisseria meningitidis carriage may be associated with transmission of the meningococcus. Our aim was to establish the impact of meningococcal B (4CMenB) vaccine on N. meningitidis carriage density.
We compared 4CMenB vaccine to control among 913 South Australian students aged approximately 15-18 years in a cluster randomized trial who had N. meningitidis carriage at 12 months. Oropharyngeal swabs were collected at baseline and 12 months later to detect N. meningitidis carriage. Colony-forming units per milliliter (CFU/mL) were estimated by generating a standard curve that plotted quantitative polymerase chain reaction cycle threshold values against log-normalized CFU.
Among the 913 students with N. meningitidis carriage at 12 months, there was no difference in mean carriage density between the vaccinated (n = 434; 3.80 log CFU/mL [standard deviation {SD}, 1.29]) and control group (n = 479; 3.73 log CFU/mL [SD, 1.30]; P = .51). Higher N. meningitidis carriage density at baseline was associated with an increase in the odds of persistent carriage at 12 months (n = 504; odds ratio [OR] per 1.0 log CFU/mL increase in density, 1.36 [95% confidence interval {CI}, 1.17-1.58]; P < .001). Students with baseline carriage who were vaccinated had decreased persistent N. meningitidis carriage at 12 months compared to unvaccinated students (81/260 [31%] vs 105/244 [43%]; OR, 0.60 [95% CI, .40-.90]; P = .01).
4CMenB vaccine did not reduce carriage density of N. meningitidis 12 months postvaccination, despite increased carriage clearance. Higher carriage density is likely to enable transmission through prolonged periods of population exposure.
NCT03089086.
脑膜炎奈瑟菌携带密度较高可能与脑膜炎奈瑟菌的传播有关。我们的目的是确定脑膜炎 B 型（4CMenB）疫苗对脑膜炎奈瑟菌携带密度的影响。
我们在一项 913 名年龄约为 15-18 岁的南澳大利亚学生的集群随机试验中，比较了 4CMenB 疫苗和对照组的效果，这些学生在 12 个月时携带脑膜炎奈瑟菌。在基线和 12 个月后采集咽拭子，以检测脑膜炎奈瑟菌的携带情况。通过生成一个标准曲线来估计每毫升的菌落形成单位（CFU/mL），该曲线绘制了定量聚合酶链反应循环阈值与对数正态化 CFU 的关系。
在 12 个月时携带脑膜炎奈瑟菌的 913 名学生中，疫苗组（n=434；3.80 log CFU/mL[标准差{SD}，1.29]）和对照组（n=479；3.73 log CFU/mL[SD，1.30]）的平均携带密度没有差异（P=0.51）。基线时较高的脑膜炎奈瑟菌携带密度与 12 个月时持续携带的几率增加相关（n=504；密度每增加 1.0 log CFU/mL，比值比[OR]为 1.36[95%置信区间{CI}，1.17-1.58]；P<0.001）。与未接种疫苗的学生相比，基线时携带且接种了疫苗的学生在 12 个月时持续携带脑膜炎奈瑟菌的比例降低（81/260[31%] vs 105/244[43%]；OR，0.60[95%CI，0.40-0.90]；P=0.01）。
尽管脑膜炎奈瑟菌清除率增加，但 4CMenB 疫苗接种后 12 个月内并未降低脑膜炎奈瑟菌的携带密度。较高的携带密度可能使传播更容易发生，从而延长人群暴露的时间。
NCT03089086。
