Development of a Novel Differential Duplex PCR for Pathogenic and Intermediate Leptospires: First Report of Intermediate Leptospira in Animal Sera in Argentina

Abstract Background: Even though leptospirosis is one of the most important zoonoses in the world, many of its aspects remain unknown, such as the distribution of different species and their pathogenicity for animals and humans. Results: Intermediate leptospiral DNA was detected in bovine sera samples from animals with abortion history from Argentina. We designed a novel duplex PCR, which differentiates pathogenic and intermediate leptospires in one single step. This new diagnostic method allowed the detection of intermediate leptospiral DNA in 4.38 % ( n = 5/114) of the total analyzed bovine samples. Conclusions: These results highlight the need of further studies of intermediate species in our country, especially regarding their association to clinical disease in animals. Remarkably, this is the first report of detection of intermediate leptospires circulating in livestock animals in Argentina and the second report in the entire world.