ETEC EPIDEMIOLOGY AND VACCINE RESEARCH IN LOWER EGYPT

产肠毒素大肠杆菌(ETEC)腹泻是一种高度地方性腹泻 埃及儿童，毒素表型分布均衡 从致病菌株中分离出来。这些功能使得开发一个 年ETEC流行病学和ETEC疫苗评估现场 埃及。我们已经开始了一项合作计划，以开发一个现场站点 亚历山大附近的儿科ETEC腹泻的研究，并评估 一种有希望的ETEC口服灭活疫苗的安全性和免疫原性 为疫苗效力的现场试验做准备的候选人。 这个项目计划跟踪了两个儿科队列，一个在Abees (亚历山大省)和阿布霍莫斯(贝海拉省) 从出生起确定ETEC腹泻的年龄别发病率 至35个月，由毒素和定居因子(CFA)表型决定； 评价血清免疫球蛋白效价之间的保护关系 ETEC毒素和CFAs抗体与ETEC引起腹泻的风险 表现出这些毒力因子。在两年的后续行动中 在242名Abees儿童中，ETEC腹泻的发病率被发现为0.9 每个孩子年的发病次数，88%的分离株仅表达LT或 仅限ST。大约四分之一的病例是由于ETEC 表达了一种公认的CFA抗原。在跟踪调查的286名儿童中， 在Abu Homos的一年中，ETEC的发病率为每 儿童年，80%的分离物仅表达LT或ST，CA。 40%的分离株表达CFA。 口服ETEC灭活剂的随机、安慰剂对照2期研究 疫苗，以两剂方案接种给附近本哈市的76名成年人 开罗，展示了疫苗的耐受性和诱导性 对疫苗抗原有显著的肌肉免疫反应。A类似的 疫苗的设计试验，接种给110名6-12岁的儿童 最近在同一地点进行了几年的调查。没有严重的反应。 注意到了，但最终的分析正在等待代码的揭开。

Enterotoxigenic Escherichia coli (ETEC) diarrhea is hyperendemic among young Egyptian children, with a balanced distribution of toxin phenotypes from pathogenic isolates. These features make it logical to develop a field site for the evaluation of ETEC epidemiology and ETEC vaccines in Egypt. We have begun a collaborative program to develop a field site near Alexandria for the study of pediatric ETEC diarrhea, and to evaluate the safety and immunogenicity of a promising killed oral ETEC vaccine candidate in preparation for a field trial of vaccine efficacy. This program of projects has followed two pediatric cohorts, one in Abees (Alexandria governorate) and the other in Abu Homos (Beheira governorate) to determine the age-specific incidence rate of ETEC diarrhea from birth to 35 months, by toxin and colonization factor (CFA) phenotype; and to evaluate the protective relationship between titers of serum IgG antibodies to ETEC toxins and CFAs and the risk of diarrhea due to ETEC manifesting these virulence factors. During two years of follow-up of 242 children in Abees, the incidence of ETEC diarrhea was found to be .9 episodes per child-year, and 88% of isolates expressed LT-only or ST-only. Approximately one-fourth of cases were due to an ETEC that expressed a recognized CFA antigen. Among the 286 children followed for one-year in Abu Homos, the incidence of ETEC was 1.4 episodes per child-year, with 80% of isolates expressing LT-only or ST-only, and ca. 40% of isolates expressed a CFA. A randomized, placebo-controlled Phase 2 study of killed oral ETEC vaccine, administered as a two-dose regimen to 76 adults in Benha, near Cairo, demonstrated the vaccine to be well-tolerated and to induce signficant musosal immune responses to vaccine antigens. A similarly designed trial of the vaccine, administered to 110 children aged 6-12 years in the same site was recently conducted. No serious reactions were noted, but definitive analyses await unblinding of the codes.