ETEC EPIDEMIOLOGY AND VACCINE RESEARCH IN LOWER EGYPT

产肠毒素大肠杆菌(ETEC)腹泻在埃及儿童中高度流行，病原菌的毒素表型分布均衡。这些特点使得在埃及开发一个用于评估ETEC流行病学和ETEC疫苗的现场站点是合乎逻辑的。我们在下埃及参与了一个合作研究项目，旨在确定ETEC腹泻在儿科队列中的特征，并测试一种有希望的口服ETEC疫苗候选疫苗的安全性和免疫原性，为1999年1月开始的疫苗效力现场试验做准备。我们在阿布霍莫斯(贝海拉省)跟踪了397名3岁以下儿童的队列，每周两次积极监测，以确定ETEC腹泻的年龄特定发病率，根据毒素和定居因子(CFA)表型。在对儿童的30个月的随访中，25%的腹泻发作中分离到ETEC；ETEC的发病率(每儿童一年的发作)在生命的第一、第二和第三年分别为1.7、1.6和0.7。在建立这项监测的同时，我们在开罗附近的本哈对口服ETEC灭活疫苗进行了随机、安慰剂对照的第二阶段研究，以两剂方案接种76名成年人、107名6-12岁的儿童、106名2-5岁的儿童和95名6-18个月大的儿童。这些研究中的每一项都证明疫苗具有良好的耐受性，并能诱导对疫苗抗原的显著粘膜免疫反应。1999年1月，在阿布霍莫斯启动了疫苗的第三阶段试验，该试验将评估疫苗的安全性、免疫原性和临床疗效。192名6-18个月大的儿童随机接受疫苗或安慰剂接种，并继续监测潜在的不良反应和腹泻结果。-产肠毒素大肠杆菌、腹泻、埃及、疫苗、临床试验-人类受试者和受试者：仅采访、问卷或调查

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 been 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, which commenced in January 1999.We have followed a cohort of 397 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 30 months of follow-up of the children, ETEC was isolated in 25% of diarrheal episodes; the incidence rates of ETEC (episodes per child-year) were 1.7, 1.6, and 0.7 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, 106 children aged 2-5 years, and 95 children aged 6-18 months in Benha, near Cairo. Each of these studies demonstrated the vaccine to be well-tolerated and to induce significant mucosal immune responses to vaccine antigens. In January 1999, a Phase III trial of the vaccine that will assess the safety, immunogenicity, and clinical efficacy of the vaccine, was initiated in Abu Homos. 192 children 6-18 months of age were randomized to receive either vaccine or placebo, and surveillance for potential adverse effects and diarrheal outcomes continues. - Enterotoxigenic Escherichia coli, diarrhea, Egypt, vaccine, clinical trial - Human Subjects & Human Subjects: Interview, Questionaires, or Surveys Only