Detection of pathogenic leptospires in the urine of domesticated elephants in Sri Lanka

•This is the first reported detection of pathogenic leptospires in urine of domesticated elephants in Sri Lanka.•Of the 13 elephants, 4 were shedding Leptospira interrogans.•Domestic elephants are in close contact with the public in Sri Lanka pose a risk of transmitting leptospirosis to humans. 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.