Investigation of Leptospirosis Agents in Cattle and Humans.

Background: Leptospirosis, a global zoonotic disease, causes serious morbidity and mortality generally in low-income societies. This study aimed to investigate the prevalence of Leptospira serovars in cattle and high-risk human populations.

Methods: This study investigated the presence of pathogenic Leptospira serogroups in the blood and kidney samples of cattle arriving at the Erzurum Meat and Milk Institution for slaughter between April and July, and between September and December 2022, and in the serum samples of humans. Kidney and serum samples from 289 cattle and serum samples from 100 individuals from at-risk occupational groups (58 farmers, 25 veterinarians and 17 butchers) were collected. As a control, 100 human blood samples were collected from civil servants who had no contact with animals. Microagglutination testing was used to investigate Leptospira serogroups in bovine sera, real-time polymerase chain reaction (PCR) for Leptospira DNA in kidney samples, and microagglutination testing and enzyme-linked immunosorbent assays for Leptospira antibodies in human blood serum samples.

Results: Microagglutination test in 4.5% of cattle; Leptospira DNA was positive in 0.7%. Six strains of Leptospira interrogans, two of Bratislava, one of Pomana and one of Icterohaemorrhagiae were found in cattle, as well as one strain of Leptospira kirschneri Dadas. In humans, two Icterohaemorrhagiae, one Hebdomadis and one Dadas serovar were detected in both the risk group and the control group. Using ELISA, antibody positivity was found to be 14.0% in the risk group and 11.0% in the control group.

Conclusion: The seroprevalence of Leptospira spp. in cattle in Erzurum, Türkiye, is relatively high. In this region, the risk of encountering Leptospira in the normal population is as high as in the risk group.