Meningitis and Vaccine Preventable Disease Branch, Division of Bacterial Diseases, National Center of Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States.
Vaccine. 2011 Jun 24;29(29-30):4739-44. doi: 10.1016/j.vaccine.2011.04.092. Epub 2011 May 13.
Neisseria meningitidis (Nm) serogroups B, C and Y are the major causes of meningococcal diseases in the United States. NmB accounts for ∼1/3 of the disease but no licensed vaccine is yet available. Two candidate vaccines are being developed specifically to target NmB, but may also provide protection against other serogroups. To assess the potential impact of these vaccines on NmB and other serogroups causing disease in the US, we determined the prevalence, genetic diversity and epidemiological characteristics of three candidate antigen genes in Nm isolates collected through Active Bacterial Core surveillance (ABCs), a population-based active surveillance program. fHbp was detected in all NmB, NmY and NmW135 isolates. Eleven NmC isolates contain fHbp with a single base-pair deletion creating a frame shift in the C-terminal region. Among NmB, 59% were FHbp subfamily/variant B/v1 and 41% A/v2-3. Among NmC and NmY, 39% and 3% were B/v1, respectively. nadA was detected in 39% of NmB, 61% of NmC and 4% of NmY. Among isolates tested, nhbA was present in all NmB and 96% of non-B. For the subset of strains sequenced for NadA and NhbA, pairwise identity was greater than 93% and 78%, respectively. The proportion of FHbp subfamily/variant was different between ABCs site and year, but no linear temporal trend was observed. Although assessment of the vaccine coverage also requires understanding of the antigen expression and the ability to induce bactericidal activity, our finding that all isolates contain one or more antigen genes suggests these candidate vaccines may protect against multiple Nm serogroups.
脑膜炎奈瑟菌（Nm）血清群 B、C 和 Y 是美国脑膜炎球菌病的主要病因。NmB 约占疾病的 1/3，但尚未有许可的疫苗。两种候选疫苗专门针对 NmB 开发，但也可能对其他血清群提供保护。为了评估这些疫苗对 NmB 和美国其他引起疾病的血清群的潜在影响，我们通过主动细菌核心监测（ABCs）确定了在 Nm 分离株中三种候选抗原基因的流行率、遗传多样性和流行病学特征，ABCs 是一项基于人群的主动监测计划。所有 NmB、NmY 和 NmW135 分离株均检测到 fHbp。11 株 NmC 分离株含有 fHbp，单个碱基缺失导致 C 末端区域移码。在 NmB 中，59%为 FHbp 亚家族/变体 B/v1，41%为 A/v2-3。在 NmC 和 NmY 中，分别有 39%和 3%为 B/v1。39%的 NmB、61%的 NmC 和 4%的 NmY 中检测到 nadA。在测试的分离株中，所有 NmB 和 96%的非 B 型均存在 nhbA。对于测序的 NadA 和 NhbA 亚组菌株，成对同一性分别大于 93%和 78%。FHbp 亚家族/变体的比例在 ABCs 地点和年份之间不同，但未观察到线性时间趋势。尽管评估疫苗覆盖率还需要了解抗原表达和诱导杀菌活性的能力，但我们发现所有分离株均含有一种或多种抗原基因，这表明这些候选疫苗可能对多种 Nm 血清群提供保护。
