Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
Epicentre, Paris, France.
BMJ Open. 2022 Jul 6;12(7):e061206. doi: 10.1136/bmjopen-2022-061206.
Cholera outbreaks in fragile settings are prone to rapid expansion. Case-area targeted interventions (CATIs) have been proposed as a rapid and efficient response strategy to halt or substantially reduce the size of small outbreaks. CATI aims to deliver synergistic interventions (eg, water, sanitation, and hygiene interventions, vaccination, and antibiotic chemoprophylaxis) to households in a 100-250 m 'ring' around primary outbreak cases.
We report on a protocol for a prospective observational study of the effectiveness of CATI. Médecins Sans Frontières (MSF) plans to implement CATI in the Democratic Republic of the Congo (DRC), Cameroon, Niger and Zimbabwe. This study will run in parallel to each implementation. The primary outcome is the cumulative incidence of cholera in each CATI ring. CATI will be triggered immediately on notification of a case in a new area. As with most real-world interventions, there will be delays to response as the strategy is rolled out. We will compare the cumulative incidence among rings as a function of response delay, as a proxy for performance. Cross-sectional household surveys will measure population-based coverage. Cohort studies will measure effects on reducing incidence among household contacts and changes in antimicrobial resistance.
The ethics review boards of MSF and the London School of Hygiene and Tropical Medicine have approved a generic protocol. The DRC and Niger-specific versions have been approved by the respective national ethics review boards. Approvals are in process for Cameroon and Zimbabwe. The study findings will be disseminated to the networks of national cholera control actors and the Global Task Force for Cholera Control using meetings and policy briefs, to the scientific community using journal articles, and to communities via community meetings.
脆弱环境中的霍乱疫情容易迅速蔓延。针对疫区的目标干预措施（CATIs）被提议作为一种快速有效的应对策略，以阻止或大幅减少小范围暴发的规模。CATI 旨在向初级暴发病例周围 100-250 米的“环”内的家庭提供协同干预措施（例如，水、环境卫生和个人卫生干预措施、疫苗接种和抗生素化学预防）。
我们报告了一项关于针对疫区目标干预措施有效性的前瞻性观察性研究的方案。无国界医生组织（MSF）计划在刚果民主共和国（DRC）、喀麦隆、尼日尔和津巴布韦实施针对疫区的目标干预措施。这项研究将与每次实施并行进行。主要结局是每个 CATI 环中的霍乱累积发病率。一旦在新地区发现病例，就会立即触发 CATI。与大多数真实世界的干预措施一样，由于该策略的推出，响应会存在延迟。我们将根据响应延迟来比较环中的累积发病率，作为性能的替代指标。横断面家庭调查将衡量基于人群的覆盖率。队列研究将衡量对减少家庭接触者发病率和改变抗生素耐药性的影响。
无国界医生组织和伦敦卫生与热带医学学院的伦理审查委员会已批准了一份通用方案。DRC 和尼日尔的特定版本已获得各自国家伦理审查委员会的批准。正在为喀麦隆和津巴布韦办理批准手续。该研究结果将通过会议和政策简报向国家霍乱控制行动者网络和全球霍乱控制工作队传播，通过期刊文章向科学界传播，并通过社区会议向社区传播。
