Seroprevalence and Molecular Characterization of spp. in Rats Captured near Pig Farms in Colombia.

Gram-negative spirochete spp. causes leptospirosis. Leptospirosis is still a neglected disease, even though it can cause potentially fatal infections in a variety of species including humans. The purpose of this study was to determine the seroprevalence of leptospirosis in pig farm captured rodents and characterize the isolated samples. Rats were captured, sampled, and euthanized in the vicinity of pig farms to obtain serum for microagglutination tests (MAT) and kidney tissues for PCR amplification of the 16S rRNA and genes. A fraction of the 16S rRNA PCR product was sequenced and phylogenetically analyzed. The results showed a seroprevalence of 13.8% (77/555) among the 555 captured rats. PCR positivity for spp. reached 31.2% (156/500), and the positivity for pathogenic spp. was 4% (22/500). Phylogenetic analysis matched eight samples with serovar icterohaemorrhagiae and two with serovar pyrogenes. Two sequences were located within the pathogenic clade but did not match with any specific strain. The seroprevalence found in the rats around swine farms indicates a potential risk of transmission to the pigs. The identification of pathogenic outlines the importance of more research as well as updating the current strategies for the diagnosis, control, and prevention of porcine leptospirosis in Colombia.