Cui X L, Wu X, Li M Q
Liuzhou Center for Disease Control and Prevention, Liuzhou 545007, China.
Zhonghua Yu Fang Yi Xue Za Zhi. 2016 Dec 6;50(12):1079-1083. doi: 10.3760/cma.j.issn.0253-9624.2016.12.011.
To understand the level of bactericidal antibodies against and their rate of protection in children aged between 3 and 23 months, in Liuzhou, in 2012. Convenience sampling was performed in Liujiang, Rong'an and Sanjiang Counties from May through August, 2012. The inclusion criteria for 603 subjects were: Children aged between 3 and 23 months; no history of meningococcal meningitis; no vaccination against serogroup C; more than 30 days from the last vaccination against serogroup A. Demographic information and immunization history of the subjects were obtained using questionnaires. Venous blood samples (2.0 ml each) were collected and levels of antibodies determined using a Serum Bactericidal Assay (SBA). The geometric mean titer (GMT) of serum bacterial antibodies was positive when it was greater than or equal to 1∶2 and protective when greater than 1∶8. Chi-square and Fisher's exact tests were used to compare differences in the positive and protective rates of serum antibodies of serogroup A and serogroup C, among children with different demographic characteristics. Kruskal-Wallis test was used to compare differences in the GMT of serum antibodies of serogroup A and serogroup C, among children with different demographic characteristics. Of 603 subjects, 325 (53.9%) were female and 278 (46.1%) were male; 276 (45.8%), 143 (23.7%) and 184 (30.5%) subjects were administered, respectively, no treatment, 1 dose vaccine and 2 doses vaccine. The GMT of serum antibodies against group A was 1∶1.11, the positive rate was 7.6% (46) and the protective rate was 2.0% (12). The GMT of antibodies in children receiving 1 vaccine dose was 1∶1.16 and the protective rate was 3.5% (5), both values higher than those in children receiving 2 vaccine doses (GMT: 1∶1.2, protective rate: 3.5% (5)). However, these differences were not statistically significant (GMT: =0.64, 0.728; protective rate: Fisher's exact test, 0.080). The GMT of antibodies in children receiving 1 and 2 doses of vaccines were 1∶1.12 and 1∶2.30, respectively (≤180 d). The GMT of serum antibodies for group C vaccine was 1∶1.18 and its positive and protective rates were 14.6% (88) and 2.2% (13), respectively. Children aged between 3 and 23 months are susceptible to groups A and C. The immune effectiveness of group A vaccine is relatively poor in this age group and their antibody levels decreased rapidly.
为了解2012年柳州市3至23个月儿童针对[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]的杀菌性抗体水平及其保护率。2012年5月至8月在柳江、融安和三江县进行了便利抽样。603名受试者的纳入标准为：年龄在3至23个月之间；无脑膜炎球菌性脑膜炎病史；未接种过C群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]疫苗；距上次接种A群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]疫苗超过30天。通过问卷调查获取受试者的人口统计学信息和免疫史。采集静脉血样本（每份2.0毫升），并使用血清杀菌试验（SBA）测定[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]抗体水平。血清细菌抗体的几何平均滴度（GMT）大于或等于1∶2时为阳性，大于1∶8时具有保护作用。采用卡方检验和Fisher精确检验比较不同人口统计学特征儿童中A群和C群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]血清抗体的阳性率和保护率差异。采用Kruskal-Wallis检验比较不同人口统计学特征儿童中A群和C群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]血清抗体GMT的差异。603名受试者中，325名（53.9%）为女性，278名（46.1%）为男性；分别有276名（45.8%）、143名（23.7%）和184名（30.5%）受试者未接受治疗、接种1剂疫苗和接种2剂疫苗。针对A群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]的血清抗体GMT为1∶1.11，阳性率为7.6%（46例），保护率为2.0%（12例）。接种1剂疫苗儿童的抗体GMT为1∶1.16，保护率为3.5%（5例），两者均高于接种2剂疫苗的儿童（GMT：1∶1.2，保护率：3.5%（5例））。然而，这些差异无统计学意义（GMT：=0.64，P = 0.728；保护率：Fisher精确检验，P = 0.080）。接种1剂和2剂[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]疫苗儿童的抗体GMT分别为1∶1.12和1∶2.30（≤180天）。C群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]疫苗的血清抗体GMT为1∶1.18，其阳性率和保护率分别为14.6%（88例）和2.2%（13例）。3至23个月的儿童易感染A群和C群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]。该年龄组A群[疫苗名称未给出，推测为某种疫苗，暂用“ ”代替]疫苗的免疫效果相对较差，其抗体水平下降迅速。
