亚洲两个发展中国家孟加拉国和越南婴幼儿五价轮状病毒疫苗的免疫原性。

Immunogenicity of the pentavalent rotavirus vaccine among infants in two developing countries in Asia, Bangladesh and Vietnam.

机构信息

International Vaccine Institute, Seoul, South Korea.

出版信息

Vaccine. 2012 Apr 27;30 Suppl 1:A106-13. doi: 10.1016/j.vaccine.2011.11.091.

DOI:10.1016/j.vaccine.2011.11.091

PMID:22520119

Abstract

BACKGROUND

We evaluated the immunogenicity of the pentavalent rotavirus vaccine (PRV) in two GAVI-eligible Asian countries, Bangladesh and Vietnam, nested in a larger randomized, double-blind, placebo-controlled efficacy trial conducted over a two-year period from 2007 through 2009.

METHODS

2036 infants were randomly assigned, in a 1:1 ratio, to receive three oral doses of PRV or placebo approximately at 6, 10, and 14 weeks of age. Concomitant use of EPI vaccines, including oral poliovirus vaccine (OPV) and diphtheria-tetanus-whole cell pertussis (DTwP) vaccine, was encouraged in accordance to the local EPI schedule. A total of 303 infants were evaluated for immunogenicity and blood samples were collected before the first dose (pD1) and approximately 14 days following the third dose (PD3). The seroresponse rates (≥3-fold rise from pD1 to PD3) and geometric mean titers (GMTs) were measured for anti-rotavirus immunoglobulin A (IgA) and serum neutralizing antibody (SNA) to human rotavirus serotypes G1, G2, G3, G4, and P1A[8], respectively.

RESULTS

Nearly 88% of the subjects showed a ≥3-fold increase in serum anti-rotavirus IgA response in the analysis of the two countries combined. When analyzed separately, the IgA response was lower in Bangladeshi children (78.1% [95% CI: 66.0, 87.5]) than in Vietnamese children (97.0% [95% CI: 89.6, 99.6]), with a PD3 GMT of 29.1 (units/mL) and 158.5 (units/mL), respectively. In the combined population, the SNA responses to the individual serotypes tested ranged from 10 (G3) to 50 (G1) percentage points lower than the responses shown in the developed countries. However, the SNA response to G3 in Vietnamese subjects was 37.3% (95% CI: 25.8, 50.0), which was similar to the G3 response rate in developed countries.

CONCLUSIONS

Three oral doses of PRV were immunogenic in two GAVI-eligible Asian countries: Bangladesh and Vietnam. The GMTs of both the serum anti-rotavirus IgA and SNA responses were generally higher in Vietnamese than in Bangladeshi children. The SNA responses varied by individual serotypes and were lower than the results from developed countries. The clinical significance of these observations is not understood because an immune correlate of protection has not been established.

摘要

背景

我们在两个符合 GAVI 资格的亚洲国家——孟加拉国和越南，评估了五价轮状病毒疫苗（PRV）的免疫原性，该研究嵌套在一项更大的、为期两年的随机、双盲、安慰剂对照功效试验中，于 2007 年至 2009 年进行。

方法

2036 名婴儿以 1:1 的比例随机分配，分别接受三剂口服 PRV 或安慰剂，大约在 6、10 和 14 周龄时接种。根据当地 EPI 计划，同时使用 EPI 疫苗，包括口服脊髓灰质炎疫苗（OPV）和白喉-破伤风-全细胞百日咳（DTwP）疫苗。共有 303 名婴儿进行了免疫原性评估，在第一次剂量（pD1）前和第三次剂量（PD3）后大约 14 天采集血样。分别测量了针对人轮状病毒血清型 G1、G2、G3、G4 和 P1A[8]的血清抗轮状病毒免疫球蛋白 A（IgA）和血清中和抗体（SNA）的血清应答率（pD1 至 PD3 时≥3 倍增加）和几何平均滴度（GMTs）。

结果

在两国联合分析中，近 88%的受试者血清抗轮状病毒 IgA 应答呈≥3 倍增加。单独分析时，孟加拉国儿童的 IgA 应答率较低（78.1%[95%CI：66.0，87.5]），低于越南儿童（97.0%[95%CI：89.6，99.6]），PD3GMT 分别为 29.1（单位/mL）和 158.5（单位/mL）。在联合人群中，针对所测试的各个血清型的 SNA 应答率比发达国家低 10（G3）至 50（G1）个百分点。然而，越南受试者对 G3 的 SNA 应答率为 37.3%（95%CI：25.8，50.0），与发达国家的 G3 应答率相似。