High prevalence of pathogenic Leptospira in wild and domesticated animals in an endemic area of China

Abstract

To assess the prevalence of Leptospira detected in wildlife and domesticated animals in Jiangxi Province, China, in. Urine samples from 28 buffaloes and kidney samples from 50 pigs, 50 dogs and 38 rats were collected from Fuliang and Shangrao County, Jiangxi Province, China, in October 2009. Polymerase chain reaction(PCR)and culture analyses were used to detect Leptospira. The cultured isolates were typed using the microscopic agglutination test(MAT). The results showed that rats potentially serve as the main reservoir of leptospiral infection, followed by dogs. Although 16% of rats (6/38) were positive using culture analysis, PCR analysis using the diagnostic primers G1/G2 and B64I/B64II or lipL32 showed identification as 50% and 24%, respectively, of the rat samples as positive for the presence of leptospiral DNA. PCR-based detection of leptospiral DNA in infected kidney tissues of reservoirs is more efficient when using G1/G2 primers than lipL32 primers. However, the latter primers have a potential application for detection in urine samples. The alarmingly high prevalence of leptospiral DNA in the wild rat population near human habitation underscores the utility of routine Leptospira surveillance, preferably using PCR methods, which are more sensitive than traditional culture-based methods.