Molecular epidemiology of rodent-bornespp. in Sri Lanka: identification of novel sequence types and previously unrecognized reservoir animals.

Abstract

Leptospirosis is an important zoonotic disease globally, which is most prevalent in tropical regions. This disease is endemic in Sri Lanka, where the complex ecology ofspp., reservoir animals and environmental and occupational factors has resulted in a public health problem.Although genomic analysis ofisolates has recently revealed the diversity ofspp. in Sri Lanka, the genetic relationship between human patients and reservoir animals remains unclear.This study investigated the genetic diversity ofspp. circulating in rodent populations in three districts of Sri Lanka: Kurunegala, Anuradhapura and Badulla.DNA was detected from rodent kidney tissue samples by real-time PCR, from which positive samples were subjected tosequencing and multilocus sequencing typing (MLST).PathogenicDNA was detected by real-time PCR in 33 of 257 kidney tissue samples (12.8%) from 4 rodent species:,,andsp. MLST and partialsequencing of real-time PCR-positive samples identified,,andin the rodent population. Five sequence types (STs), including two novel STs, ST389 and ST392, were identified. The novel STs ofandwere genetically distinct from other STs detected in Sri Lanka.andwere newly identified as the source ofST49 and ofST144 andinfections in humans, respectively.This study identified the genetic diversity ofspp. in rodent populations and reservoir animals for human infections in Sri Lanka.