越南芽庄人群对白喉类毒素 IgG 抗体的血清阳性率、衰减率和保护持续时间。

The seroprevalence, waning rate, and protective duration of anti-diphtheria toxoid IgG antibody in Nha Trang, Vietnam.

机构信息

Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK; School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan; Department of Pediatric Infectious Diseases, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.

Department of Microbiology and Immunology, Pasteur Institute in Nha Trang, Nha Trang, Vietnam.

出版信息

Int J Infect Dis. 2022 Mar;116:273-280. doi: 10.1016/j.ijid.2022.01.025. Epub 2022 Jan 19.

DOI:10.1016/j.ijid.2022.01.025

PMID:35063678

Abstract

BACKGROUND

Diphtheria cases reported in Central Vietnam since 2013 were mainly in children aged 6-15 years, which may reflect an immunity gap. There is little information on population immunity against diphtheria in countries without a school-entry booster dose. We aimed to measure the age-stratified seroprevalence of anti-diphtheria toxoid antibodies, quantify the change in antibody levels in individuals over time, and estimate the length of protective immunity after vaccination in well-vaccinated communities in Vietnam.

METHODS

An age-stratified seroprevalence survey among individuals aged 0-55 years was conducted at Nha Trang, Vietnam. The same participants were followed up after two years to quantify the change in antibody levels. IgG was measured using ELISA. The length of protective immunity after vaccination was estimated using a mixed-effect linear regression model with random intercept.

RESULTS

Overall seroprevalence was 26% (95%CI:20-32%). Age-stratified seroprevalence was 68% (95%CI:4-11%), 7% (95%CI:4-11%), 12% (95%CI:7-19%), 33% (95%CI:27-40%), and 28% (95%CI:17-43%) among those aged ≤5, 6-15,16-25, 26-35, and 36-55 years, respectively. The antibody levels declined by 47% (95%CI:31-59%) over two years, and the predicted duration of vaccine-derived protective immunity after receiving four doses was 4.3 years (95%CI:3.5-5.3) among participants aged six years or younger.

CONCLUSION

Given the low seroprevalence and short period of vaccine protection, a school-entry booster dose (5-7 years) is recommended in Vietnam.

摘要

背景

自 2013 年以来，越南中部报告的白喉病例主要发生在 6-15 岁儿童中，这可能反映了免疫空白。在没有入学加强剂量的国家，关于人群对白喉的免疫力的信息很少。我们的目的是测量按年龄分层的抗白喉类毒素抗体的血清阳性率，量化个体随时间抗体水平的变化，并估计在越南免疫良好的社区中接种疫苗后的保护免疫力持续时间。

方法

在越南芽庄进行了一项按年龄分层的血清阳性率调查，其中包括 0-55 岁的个体。两年后对同一参与者进行随访，以量化抗体水平的变化。使用 ELISA 测量 IgG。使用具有随机截距的混合效应线性回归模型估计接种疫苗后的保护免疫力持续时间。

结果

总体血清阳性率为 26%（95%CI：20-32%）。按年龄分层的血清阳性率为 68%（95%CI：4-11%）、7%（95%CI：4-11%）、12%（95%CI：7-19%）、33%（95%CI：27-40%）和 28%（95%CI：17-43%），分别为≤5 岁、6-15 岁、16-25 岁、26-35 岁和 36-55 岁。两年后，抗体水平下降了 47%（95%CI：31-59%），在 6 岁或以下的参与者中，接受四剂疫苗后，疫苗衍生的保护免疫力持续时间预计为 4.3 年（95%CI：3.5-5.3）。