Serological and molecular evidence of Leptospira spp. in martens from Poland.

Background
Leptospirosis is a globally-distributed zoonotic disease caused by pathogenic Leptospira spp., affecting humans, domestic animals, and wildlife. Despite its importance, little is known about the ecological and epidemiological aspects of Leptospira spp. infection in wild carnivores, particularly martens. This study investigated the presence of Leptospira spp. in stone martens (Martes foina) and pine martens (Martes martes) in northern Poland using serological (MAT) and molecular (real-time PCR and MLST) methods.Results
Samples from 129 martens collected between 2012 and 2022 revealed an 18% seroprevalence and a 13% PCR-positivity rate. Seroreactivity against six Leptospira spp. serovars was identified, all associated with rodent transmission cycles.. Molecular analysis confirmed the presence of sequence types ST117 and ST110, previously reported in small mammals in Central Europe.Conclusions
Martens are susceptible hosts for Leptospira spp.. Given their adaptability and overlapping habitats with livestock and humans, they also represent valuable targets for integrated surveillance within the One Health framework. This study provides the first evidence of Leptospira spp. sequence types and serological diversity in martens in Poland, and offers valuable insights into the epidemiology of wildlife leptospirosis.