Leptospira infection among human-close-contact animals in different geographical areas in Vietnam

Leptospirosis is a neglected disease in Vietnam. Only a few studies have evaluated the status of Leptospira infection in both humans and animals. To our knowledge, this is the first serological survey of Leptospira in both domestic and wild animals, which may act as reservoirs of this agent. This study aimed to evaluate the seroprevalence of Leptospira in animals that are in close contact with humans in different geographical areas in Vietnam. Sera were collected from 1205 individual animals of six species, including buffaloes, cattle, cats, dogs, swine, and rats. The microscopic agglutination test (MAT) against 25 serovars of Leptospira spp. has been employed to detect serovars of Leptospira among the studied population. Overall, 44.2% of buffaloes, 24.9% of cattle, 10.2% of swine, 32.9% of dogs, 12.2% of cats, and 16% of rats were seropositive. A total of 17 different serovars were detected, of which serovars Hebdomadis and Canicola circulated in all the studied animal species. Variability of the predominant serovars circulating in animal species and in different geographical areas of Vietnam has been noted. We conclude that this study showed a high prevalence of Leptospira circulating in animals that are in close contact with humans, raising an alert of the important sources of pathogenic leptospires transmission to humans in Vietnam. These findings prove an imperative need for effective measures for disease prevention.