Contact Mag.med.vet. Cynthia Sohm: cynthia.sohm@vetmeduni.ac.at Acknowledgements This project was founded by the federal state of Lower Austria. Grant number WST3-F-5033836/001–2020 • Isolate and genotype circulating Leptospira strains from cattle in Austria, to enhance the performances of the serological diagnostic test for humans and animals. • Further the understanding of the local epidemiology of this zoonotic disease. Goals • Inclusion criteria: a) High-risk farms: Farms presenting two of these four characteristics: > 34 head of cattle on the farm, introducing new cattle (buying), access to pasture, history of abortions. b) Symptomatic cattle: Cattle presenting one of these six symptoms: abortion, fertility disorder, photosensitisation, icterus, haematuria, decrease in milk yield. Older cattle were prioritised, no systemic antibiotic treatment within two weeks prior to the sampling. • PCR: • 5/410 (1.2%) cattle positive. • Six urine samples (from four cattle) and three kidney samples. • Sequencing lfb1 gene: Successful in 5/6 urine samples: all identified as Leptospira borgpetersenii. • Culture: • Three isolates from the three PCR positive kidney samples. • Growth detected after seven, 18 and 23 weeks of cultivation. • Required addition of foetal calf serum (FCS). • cgMLST: All three isolates were identified as Leptospira borgpetersenii serogroup Sejroe, serovar Hardjobovis [5]. Results • First isolation and subsequent genotyping of locally circulating pathogenic Leptospira in Austria. • Initial step towards enhancing the performances of the serological diagnostics for both humans and animals withing the country. • Cattle may act as carrier of pathogenic Leptospira in Austria. • Zoonotic potential of the identified circulating strain. Farmers, veterinarians & slaughterhouse workers at higher risk of infection. • Leptospirosis should be considered as differential diagnosis for bovine abortions in Austrian cattle. Conclusion 1 Haake DA & Levett PN. (2015). Leptospirosis in humans. In: Adler B, editor. Leptospira and leptospirosis. Current Topics in Microbiology and Immunology. Vol. 387. Berlin, Heidelberg: Springer Berlin Heidelberg. p. 65–97. 2 O’ Doherty E, et al. (2015). Effect of exposure to Neospora caninum, Salmonella, and Leptospira interrogans serovar Hardjo on the economic performance of Irish dairy herds. J Dairy Sci 98 (4): 2789–800. DOI 10.3168/jds.2014-8168 3 World Health Organization (WHO). Leptospirosis laboratory manual https:// www. who. int/ publi catio ns/i/ item/ B2147 (2007). 4 World Organisation for Animal Health (WOAH). 3.1.12 Leptospirosis in Manual of Diagnostic Tests and Vaccines for Terrestrial Animals 2022 https:// www. woah. org/ filea dmin/ Home/ fr/ Health_ stand ards/ tahm/3. 01. 12_ LEPTO. pdf (World Organisation for Animal Health, 2021) 5 Sohm C, et al. 2024. First isolation and genotyping of pathogenic Leptospira spp. from Austria. Sci Rep 14 (1): 1–9. DOI 10.1038/s41598-024-53775-w. References • Leptospirosis is a globally spread zoonotic disease, which mainly affects humans and mammals. • The disease is caused by pathogenic bacteria of the genus Leptospira. • In humans the symptoms range from mild, influenza-like syndrome to the potentially deadly Weil’s disease [1]. • In cattle, abortions and fertility disorders are common signs of infection. Therefore, leptospirosis can lead to significant financial losses [2]. • The microscopic agglutination test is the gold standard for the sero-diagnosis. The World Health Organization and the World Organisation for Animal Health recommend the inclusion of locally circulating strains in the panel of live strains [3,4]. • In Austria no local strain has been available for diagnostic purposes. Background • Targeted sampling: Based on a systematic literature review and analysis of national serological data. • Urine and/or kidney samples of: a) Routinely slaughtered cattle from identified high-risk farms located in Lower Austria, and b) Cattle from farms