Uganda Public Health Fellowship Program, Kampala, Uganda.
Ministry of Health, Kampala, Uganda.
Infect Dis Poverty. 2020 Nov 4;9(1):154. doi: 10.1186/s40249-020-00761-9.
On 23 February 2018, the Uganda Ministry of Health (MOH) declared a cholera outbreak affecting more than 60 persons in Kyangwali Refugee Settlement, Hoima District, bordering the Democratic Republic of Congo (DRC). We investigated to determine the outbreak scope and risk factors for transmission, and recommend evidence-based control measures.
We defined a suspected case as sudden onset of watery diarrhoea in any person aged ≥ 2 years in Hoima District, 1 February-9 May 2018. A confirmed case was a suspected case with Vibrio cholerae cultured from a stool sample. We found cases by active community search and record reviews at Cholera Treatment Centres. We calculated case-fatality rates (CFR) and attack rates (AR) by sub-county and nationality. In a case-control study, we compared exposure factors among case- and control-households. We estimated the association between the exposures and outcome using Mantel-Haenszel method. We conducted an environmental assessment in the refugee settlement, including testing samples of stream water, tank water, and spring water for presence of fecal coliforms. We tested suspected cholera cases using cholera rapid diagnostic test (RDT) kits followed by culture for confirmation.
We identified 2122 case-patients and 44 deaths (CFR = 2.1%). Case-patients originating from Demographic Republic of Congo were the most affected (AR = 15/1000). The overall attack rate in Hoima District was 3.2/1000, with Kyangwali sub-county being the most affected (AR = 13/1000). The outbreak lasted 4 months, which was a multiple point-source. Environmental assessment showed that a stream separating two villages in Kyangwali Refugee Settlement was a site of open defecation for refugees. Among three water sources tested, only stream water was feacally-contaminated, yielding > 100 CFU/100 ml. Of 130 stool samples tested, 124 (95%) yielded V. cholerae by culture. Stream water was most strongly associated with illness (odds ratio [OR] = 14.2, 95% CI: 1.5-133), although tank water also appeared to be independently associated with illness (OR = 11.6, 95% CI: 1.4-94). Persons who drank tank and stream water had a 17-fold higher odds of illness compared with persons who drank from other sources (OR = 17.3, 95% CI: 2.2-137).
Our investigation demonstrated that this was a prolonged cholera outbreak that affected four sub-counties and two divisions in Hoima District, and was associated with drinking of contaminated stream water. In addition, tank water also appears to be unsafe. We recommended boiling drinking water, increasing latrine coverage, and provision of safe water by the District and entire High Commission for refugees.
2018 年 2 月 23 日，乌干达卫生部（MOH）宣布霍乱疫情爆发，影响了位于与刚果民主共和国（DRC）接壤的霍伊马区 Kyangwali 难民营的 60 多人。我们进行了调查，以确定疫情范围和传播的危险因素，并提出基于证据的控制措施。
我们将任何年龄≥2 岁的人在霍伊马区突然出现水样腹泻定义为疑似病例，时间为 2018 年 2 月 1 日至 5 月 9 日。确诊病例是从粪便样本中培养出霍乱弧菌的疑似病例。我们通过在霍乱治疗中心进行主动社区搜索和记录复查来发现病例。我们按次县和国籍计算了病死率（CFR）和发病率（AR）。在病例对照研究中，我们比较了病例和对照家庭的暴露因素。我们使用 Mantel-Haenszel 法估计暴露与结局之间的相关性。我们在难民营进行了环境评估，包括检测溪流、水箱和泉水水样中粪便大肠菌群的存在情况。我们使用霍乱快速诊断检测（RDT）试剂盒对疑似霍乱病例进行检测，然后进行培养以确认。
我们确定了 2122 例病例和 44 例死亡（CFR=2.1%）。来自刚果民主共和国的病例患者受影响最大（AR=15/1000）。霍伊马区的总发病率为 3.2/1000，Kyangwali 次县受影响最大（AR=13/1000）。疫情持续了 4 个月，是多点源疫情。环境评估显示，将两个村庄隔开的一条溪流是难民进行露天排便的地点。在检测的三个水源中，只有溪流的水受到粪便污染，产率>100CFU/100ml。在检测的 130 份粪便样本中，124 份（95%）通过培养检出霍乱弧菌。溪流水与疾病最密切相关（比值比[OR] = 14.2，95%CI：1.5-133），尽管水箱水似乎也与疾病独立相关（OR=11.6，95%CI：1.4-94）。与饮用其他来源水的人相比，饮用水箱和溪流水的人患病的几率高 17 倍（OR=17.3，95%CI：2.2-137）。
我们的调查表明，这是一场持续时间较长的霍乱疫情，影响了霍伊马区的四个次县和两个分区，并与饮用受污染的溪流水有关。此外，水箱水似乎也不安全。我们建议煮沸饮用水，增加厕所覆盖范围，并由区和整个难民专员办事处提供安全用水。
