Detection and differentiation of leptospires using real-time polymerase chain reaction

Abstract

Leptospirosis, an important emerging infectious disease of man and animals world-wide, is caused by helical motile spirochetes of the genus Leptospira necessity. In the present study, primer’s targeting the locus LA0322 of L. interrogans was used to compare the efficiency of conventional and SYBR green based real-time PCR assay. In serum and urine samples spiked with known amount of leptospires the conventional PCR had a average detection limit of 3.2–4.6 × 103 while real-time PCR was sensitive enough to detect as minimum as 32 to 41 leptospires per milliliter. Melting curve analysis indicated an average Tm of 79.5°C for L. interrogans, while it was for 85.6°C L. borgpetersenii. Our results indicate the ability of real-time PCR to differentiate leptospires in a single tube reaction. Further studies are required with the inclusion of other serovars.