Athapattu Tarindi Pathmila Jayanandri, Fernando Biyagamage Ruchika, Koizumi Nobuo, Gamage Chandika Damesh
Department of Veterinary Public Health and Pharmacology, Faculty of Veterinary Medicine and Animal Science, University of Peradeniya, Sri Lanka.
Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan.
Acta Trop. 2019 Jul;195:78-82. doi: 10.1016/j.actatropica.2019.04.029. Epub 2019 Apr 29.
Leptospirosis is a globally common zoonotic infectious disease in humans and animals. This disease is caused by pathogenic spirochetes belonging to the genus Leptospira. The pathogen is able to survive in mammalian kidneys after infection and is excreted in urine intermittently. Pathogenic leptospires infect humans either by direct contact with infected animal urine or through contaminated soil or water. In Sri Lanka, some studies have demonstrated the involvement of animals, such as livestock species and peridomestic rats, in the transmission of leptospirosis to humans. However, none of the previous studies focused on domesticated elephants, which are in close contact with humans during cultural and religious events and bathe in rivers together with humans. If domesticated elephants act as carriers of pathogenic leptospires, it could be a major public health issue in the country. In this study, 13 healthy domesticated elephants were subjected to leptospiral DNA detection from urine samples collected on three consecutive days. Four elephants (31%) were confirmed to shed pathogenic leptospires in their urine. DNA sequencing followed by phylogenetic distance measurements revealed that all positive elephants were infected with L. interrogans. This study reveals the possibility that elephants act as a source of infection of leptospires to humans and recommends the screening of all domesticated elephants that are in close contact with humans for the shedding of pathogenic leptospires.
钩端螺旋体病是一种在人类和动物中全球普遍存在的人畜共患传染病。该疾病由钩端螺旋体属的致病性螺旋体引起。病原体在感染后能够在哺乳动物肾脏中存活，并间歇性地随尿液排出。致病性钩端螺旋体通过直接接触受感染动物的尿液或通过受污染的土壤或水感染人类。在斯里兰卡，一些研究表明牲畜和家鼠等动物参与了钩端螺旋体病向人类的传播。然而，以前的研究均未关注家养大象，它们在文化和宗教活动期间与人类密切接触，并与人类一起在河中沐浴。如果家养大象充当致病性钩端螺旋体的携带者，这可能成为该国的一个重大公共卫生问题。在本研究中，对13头健康的家养大象连续三天采集的尿液样本进行钩端螺旋体DNA检测。四头大象（31%）被证实尿液中排出致病性钩端螺旋体。DNA测序及随后的系统发育距离测量显示，所有阳性大象均感染了问号钩端螺旋体。本研究揭示了大象可能作为人类钩端螺旋体感染源的可能性，并建议对所有与人类密切接触的家养大象进行致病性钩端螺旋体排出情况的筛查。
