ETEC EPIDEMIOLOGY AND VACCINE RESEARCH IN LOWER EGYPT

产肠毒素大肠杆菌（ETEC）腹泻在 年轻的埃及儿童，毒素表型分布均衡 从病原分离物中分离出来。 这些特征使得开发一个 评价ETEC流行病学和ETEC疫苗的现场 埃及 我们正在进行一项合作研究计划， 埃及旨在描述儿科队列中ETEC腹泻的特征， 检测有希望杀死的口服ETEC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疫苗。 我们跟踪了一组3岁以下的儿童，每周两次， 在Abu Homos（Beheira省）进行积极监测，以确定 按毒素和定植列出的ETEC腹泻的年龄特异性发病率 因子（CFA）表型。在18个月的随访期间， 在检测到的1232株大肠杆菌中，有290株（24%）分离出ETEC 事件; ETEC的发生率（每儿童年的事件）为1.5， 1.6，0.8在第一，第二，第三年的生活。并发 随着这项监测的建立，我们进行了随机， 口服ETEC灭活疫苗的安慰剂对照II期研究， 作为两剂方案给予76名成人，107名6-12岁的儿童 在开罗附近的Benha，有106名2至5岁的儿童。中的每 这些研究表明疫苗耐受性良好， 对疫苗抗原有显著的免疫应答。 类似 将启动针对婴儿的疫苗设计试验 在接下来的几个月里。

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 are engaged in a collaborative program of research in lower Egypt designed to characterize ETEC diarrhea in a pediatric cohort and to test the safety and immunogenicity of a promising killed oral ETEC vaccine candidate in preparation for a field trial of vaccine efficacy. We have followed a cohort of children under 3 years with twice-weekly active surveillance in Abu Homos (Beheira governorate) to determine the age-specific incidence rate of ETEC diarrhea, by toxin and colonization factor (CFA) phenotypes. During 18 months of follow-up of 288 children in Abu Homos, ETEC was isoalted in 290 (24%) of the 1232 detected diarrheal episodes; the incidence rates of ETEC (episodes per child-year) were 1.5, 1.6, and 0.8 in the first, second, and third years of life. Concurrent with establishment of this surveillance, we conducted randomized, placebo-controlled Phase 2 studies of killed oral ETEC vaccine, administered as a two-dose regimen to 76 adults, 107 children aged 6-12 years, and and 106 children aged 2-5 years in Benha, near Cairo. Each of these studies demonstrated the vaccine to be well-tolerated and to induce significant musosal immune responses to vaccine antigens. A similarly designed trial of the vaccine, administered to infants will be launched during the coming months.