Molecular Evidence of Leptospira spp. Infection Among Household Dogs From 15 Municipalities of the Department of Caldas, Colombia

Introduction: Leptospira spp. is a bacterial genus which includes pathogenic species that causes leptospirosis. Several animal species can harbour, shed and disseminate the bacteria through their urine. Although the circulation of Leptospira among homeless dogs may be common, the presence of Leptospira among household dogs is more important since they can act as important sources of infection for their owners due to the closer contact with humans.

Aim: The aim of the present study was to detect the presence of Leptospira spp. among household dogs from 15 municipalities of the Caldas department.

Methods: Between November 2015 and January 2017, an active household dog sampling was performed in 15 municipalities of Caldas department. Dog blood samples were tested through conventional PCR targeting a fragment of the Leptospira rrs and LipL32 genes. All obtained amplicons were purified and bi-directionally sequenced. Obtained sequences were assembled and edited for subsequent phylogenetic analysis.

Results: A total of 196 dogs were sampled from 15 municipalities of Caldas department, of which 180 were screened for Leptospira spp. Ten (5.6%) dog blood samples from seven municipalities were successfully amplified for the Leptospira rrs gene. Two Leptospira rrs good-quality sequences were obtained which had a closer relationship with Leptospira interrogans and Leptospira santarosai.

Conclusion: We confirm the presence of Leptospira spp. closely related with L. interrogans and L. santarosai among household dogs from seven municipalities of Caldas department. These results highlight the need to improve the care of household dogs in Caldas department since they could eventually become important sources of infection of leptospirosis.