London School of Hygiene & Tropical Medicine, London, UK
Médecins Sans Frontières, Brussels, Belgium.
BMJ Open. 2021 Oct 14;11(10):e050943. doi: 10.1136/bmjopen-2021-050943.
Household contacts of cholera cases are at a greater risk of infection than the general population. There is currently no agreed standard of care for household contacts, despite their high risk of infection, in cholera response strategies. In 2018, hygiene kit distribution and health promotion was recommended by Médecins Sans Frontières for admitted patients and accompanying household members on admission to a cholera treatment unit in the Democratic Republic of Congo.
To investigate the effectiveness of the intervention and risk factors for cholera infection, we conducted a prospective cohort study and followed household contacts for 7 days after patient admission. Clinical surveillance among household contacts was based on self-reported symptoms of cholera and diarrhoea, and environmental surveillance through the collection and analysis of food and water samples.
From 94 eligible households, 469 household contacts were enrolled and 444 completed follow-up. Multivariate analysis suggested evidence of a dose-response relationship with increased kit use associated with decreased relative risk of suspected cholera: household contacts in the high kit-use group had a 66% lower incidence of suspected cholera (adjusted risk ratio (aRR) 0.34, 95% CI 0.11 to 1.03, p=0.055), the mid-use group had a 53% lower incidence (aRR 0.47, 95% CI 0.17 to 1.29, p=1.44) and low-use group had 22% lower incidence (aRR 0.78, 95% CI 0.24 to 2.53, p=0.684), compared with household contacts without a kit. Drinking water contamination was significantly reduced among households in receipt of a kit. There was no significant effect on self-reported diarrhoea or food contamination.
The integration of a hygiene kit intervention to case-households may be effective in reducing cholera transmission among household contacts and environmental contamination within the household. Further work is required to evaluate whether other proactive localised distribution among patients and case-households or to households surrounding cholera cases can be used in future cholera response programmes in emergency contexts.
霍乱病例的家庭接触者比一般人群更容易感染。尽管家庭接触者感染的风险很高，但在霍乱应对策略中，目前还没有针对他们的公认护理标准。2018 年，无国界医生组织建议在刚果民主共和国的一个霍乱治疗单位为入院患者及其随行的家庭接触者发放卫生包并进行健康宣传。
为了调查干预措施的效果和霍乱感染的危险因素，我们进行了一项前瞻性队列研究，并在患者入院后 7 天内对家庭接触者进行随访。家庭接触者的临床监测基于霍乱和腹泻的自我报告症状，环境监测则通过收集和分析食物和水样进行。
从 94 个合格家庭中，招募了 469 个家庭接触者，其中 444 个完成了随访。多变量分析表明，套件使用量与疑似霍乱的相对风险降低之间存在剂量-反应关系：高套件使用组的家庭接触者疑似霍乱的发病率降低了 66%（调整后的风险比（aRR）为 0.34，95%置信区间（CI）为 0.11 至 1.03，p=0.055），中套件使用组的发病率降低了 53%（aRR 为 0.47，95%CI 为 0.17 至 1.29，p=1.44），低套件使用组的发病率降低了 22%（aRR 为 0.78，95%CI 为 0.24 至 2.53，p=0.684），与没有套件的家庭接触者相比。收到套件的家庭饮用水污染明显减少。套件的使用对自我报告的腹泻或食物污染没有显著影响。
将卫生包干预措施纳入病例家庭可能有助于减少家庭接触者之间的霍乱传播和家庭内的环境污染。需要进一步研究评估，在未来的紧急情况下，针对霍乱病例和病例家庭或病例周围家庭，是否可以采用其他主动的局部分发方式，用于霍乱应对方案。
