Centre for Microbiology Research, Kenya Medical Research Institute, Off Mbagathi Road, PO Box 54840-00200, Nairobi, Kenya.
Centre for Public Health Research, Kenya Medical Research Institute, Nairobi, Kenya.
BMC Infect Dis. 2020 Jun 17;20(1):422. doi: 10.1186/s12879-020-05134-z.
In Kenya, typhoid fever and invasive non-typhoidal salmonellosis present a huge burden of disease, especially in poor-resource settings where clean water supply and sanitation conditions are inadequate. The epidemiology of both diseases is poorly understood in terms of severity and risk factors. The aim of the study was to determine the disease burden and spatial distribution of salmonellosis, as well as socioeconomic and environmental risk factors for these infections, in a large informal settlement near the city of Nairobi, from 2013 to 2017.
Initially, a house-to-house baseline census of 150,000 population in Mukuru informal settlement was carried out and relevant socioeconomic, demographic, and healthcare utilization information was collected using structured questionnaires. Salmonella bacteria were cultured from the blood and faeces of children < 16 years of age who reported at three outpatient facilities with fever alone or fever and diarrhea. Tests of association between specific Salmonella serotypes and risk factors were conducted using Pearson Chi-Square (χ) test.
A total of 16,236 children were recruited into the study. The prevalence of bloodstream infections by Non-Typhoidal Salmonella (NTS), consisting of Salmonella Typhimurium/ Enteriditis, was 1.3%; Salmonella Typhi was 1.4%, and this was highest among children < 16 years of age. Occurrence of Salmonella Typhimurium/ Enteriditis was not significantly associated with rearing any domestic animals. Rearing chicken was significantly associated with high prevalence of S. Typhi (2.1%; p = 0.011). The proportion of children infected with Salmonella Typhimurium/ Enteriditis was significantly higher in households that used water pots as water storage containers compared to using water directly from the tap (0.6%). Use of pit latrines and open defecation were significant risk factors for S. Typhi infection (1.6%; p = 0.048). The proportion of Salmonella Typhimurium/ Enteriditis among children eating street food 4 or more times per week was higher compared to 1 to 2 times/week on average (1.1%; p = 0.032).
Typhoidal and NTS are important causes of illness in children in Mukuru informal settlement, especially among children less than 16 years of age. Improving Water, Sanitation and Hygiene (WASH) including boiling water, breastfeeding, hand washing practices, and avoiding animal contact in domestic settings could contribute to reducing the risk of transmission of Salmonella disease from contaminated environments.
在肯尼亚，伤寒和侵袭性非伤寒沙门氏菌病给当地带来了沉重的疾病负担，特别是在水源供应和卫生条件不足的资源匮乏地区。这两种疾病的流行病学特征及其相关的严重程度和危险因素尚未得到充分了解。本研究的目的是确定内罗毕市附近一个大型非正规住区在 2013 年至 2017 年期间的沙门氏菌病疾病负担和空间分布，以及这些感染的社会经济和环境危险因素。
最初，对 Mukuru 非正规住区的 15 万人口进行了逐户基线普查，并使用结构化问卷收集了相关的社会经济、人口统计和医疗保健利用信息。对在三家门诊机构就诊的发热儿童（无论是否腹泻）采集血样和粪便，培养沙门氏菌。使用 Pearson Chi-Square (χ) 检验检测特定沙门氏菌血清型与危险因素之间的关联。
共招募了 16236 名儿童参与研究。非伤寒沙门氏菌（NTS）血流感染的患病率为 1.3%，其中包括肠炎沙门氏菌/鼠伤寒沙门氏菌；伤寒沙门氏菌的患病率为 1.4%，在 16 岁以下儿童中最高。饲养任何家畜与肠炎沙门氏菌/鼠伤寒沙门氏菌的发生均无显著相关性。饲养鸡与高流行率的伤寒沙门氏菌显著相关（2.1%；p=0.011）。与直接从水龙头接水相比，使用水罐作为储水容器的家庭中肠炎沙门氏菌/鼠伤寒沙门氏菌感染儿童的比例显著更高（0.6%）。使用坑式厕所和露天排便为伤寒沙门氏菌感染的显著危险因素（1.6%；p=0.048）。每周食用街头食品 4 次或以上的儿童感染肠炎沙门氏菌/鼠伤寒沙门氏菌的比例高于每周 1-2 次的儿童（1.1%；p=0.032）。
伤寒和 NTS 是 Mukuru 非正规住区儿童患病的重要原因，尤其是 16 岁以下儿童。改善水、环境卫生和个人卫生（WASH），包括煮沸水、母乳喂养、洗手习惯以及避免家中动物接触，可能有助于降低从污染环境传播沙门氏菌病的风险。
