College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.
Gihundwe District Hospital, Rusizi, Rwanda.
PLoS Negl Trop Dis. 2021 Dec 7;15(12):e0009708. doi: 10.1371/journal.pntd.0009708. eCollection 2021 Dec.
Leptospirosis is a zoonotic disease transmitted through the urine of wild and domestic animals, and is responsible for over 50,000 deaths each year. In East Africa, prevalence varies greatly, from as low as 7% in Kenya to 37% in Somalia. Transmission epidemiology also varies around the world, with research in Nicaragua showing that rodents are the most clinically important, while studies in Egypt and Chile suggest that dogs may play a more important role. There are no published studies of leptospirosis in Rwanda.
METHODS & FINDINGS: We performed a cross-sectional survey of asymptomatic adults recruited from five occupational categories. Serum samples were tested using ELISA and Microscopic Agglutination Test (MAT). We found that 40.1% (151/377) of asymptomatic adults had been exposed to Leptospira spp. Almost 36.3% of positive subjects reported contact with rats (137/377) which represent 90.7% among positive leptospira serology compared with 48.2% of negative subjects (182/377) which represent 80.5% among negative leptospira serology (OR 2.37, CI 1.25-4.49) and 1.7 fold on prevalence ratio and 2.37 of odd ratio. Furthermore, being a crop farmer was significantly associated with leptospirosis (OR 2.06, CI 1.29-3.28). We identified 6 asymptomatic subjects (1.6%) who met criteria for acute infection.
This study demonstrates a high prevalence of leptospiral antibodies infection among asymptomatic adults in rural Rwanda, particularly relative to neighboring countries. Although positive subjects were more likely to report rat contact, we found no independent association between rats and leptospirosis infection. Nonetheless, exposure was high among crop farmers, which is supportive of the hypothesis that rats together with domestic livestock might contribute to the transmission. Further studies are needed to understand infecting Leptospira servers and elucidate the transmission epidemiology in Rwanda and identify means of host transmitters.
钩端螺旋体病是一种通过野生动物和家畜尿液传播的人畜共患病，每年导致超过 50000 人死亡。在东非，流行率差异很大，从肯尼亚的 7%到索马里的 37%不等。传播流行病学也因世界各地而异，尼加拉瓜的研究表明啮齿动物是最重要的临床类型，而埃及和智利的研究表明狗可能发挥更重要的作用。卢旺达尚无钩端螺旋体病的发表研究。
我们对来自五个职业类别的无症状成年人进行了横断面调查。使用 ELISA 和显微镜凝集试验 (MAT) 检测血清样本。我们发现，40.1%（151/377）的无症状成年人曾接触过钩端螺旋体属。几乎 36.3%的阳性患者报告与老鼠接触（137/377），这在阳性钩端螺旋体血清学中占 90.7%，而在阴性患者中占 48.2%（182/377），占阴性钩端螺旋体血清学的 80.5%（OR 2.37，CI 1.25-4.49），在患病率比上为 1.7 倍，比值比为 2.37。此外，作为农作物种植者与钩端螺旋体病显著相关（OR 2.06，CI 1.29-3.28）。我们发现了 6 名符合急性感染标准的无症状患者（1.6%）。
本研究表明，卢旺达农村地区无症状成年人中钩端螺旋体抗体感染的患病率很高，尤其是与邻国相比。尽管阳性患者更有可能报告与老鼠接触，但我们没有发现老鼠与钩端螺旋体病感染之间存在独立的关联。尽管如此，农作物种植者的接触率仍然很高，这支持了老鼠与家畜一起可能导致传播的假设。需要进一步研究以了解感染钩端螺旋体的血清型并阐明卢旺达的传播流行病学，并确定宿主传播者的方法。
