100 Cent Eur J Public Health 2015; 23 (2): 100–106 SUMMARY Objective: The aim of the study was to determine the seroprevalence of three zoonotic infections among healthy blood donors/volunteers in Eastern Slovakia. Methods: Sera from 124 blood donors were investigated for the presence of antibodies against Borrelia burgdorferi, Francisella tularensis and Leptospira pomona. The participants also completed the questionnaire about demographic, exposure and epidemiological characteristics. Two serological methods were used for the diagnosis: the enzyme linked protein A/G assay (ELPAGA) and the Western blot (WB). First, sera were screened by ELPAGA (except for leptospirosis). Results: The observed seroprevalence was 15% for Lyme borreliosis (LB) and 4% for tularaemia (TUL). The results were confirmed by WB. Positive IgG antibodies (WB method) were detected only in 1.6% of examined for LB and 0.8% for TUL. Our results did not identify any antibodies against Leptospira pomona agent in the examined healthy blood donors group. Conclusions: ELPAGA seroprevalence for TUL was significantly higher in blood donors working in the agricultural area in the direct contact with hay, straw, manure, and agricultural land. Our outputs determine tick bite as a significant risk factor for LB. The study confirms the explosion of tick-borne diseases in the healthy population of people. The exposure risk for leptospirosis seems to be minimal. Key words: Lyme disease, tularaemia, leptospirosis, seroprevalence, blood donors, Slovakia Address for correspondence: E. Dorko, Department of Public Health and Hygiene, Faculty of Medicine, P. J. Šafárik University, Šrobárova 2, 040 80 Košice, Slovak Republic. E-mail: erik.dorko@upjs.sk PILOT CROSS-SECTIONAL STUDY OF THREE ZOONOSES (LYME DISEASE, TULARAEMIA, LEPTOSPIROSIS) AMONG HEALTHY BLOOD DONORS IN EASTERN SLOVAKIA Ľubica Zákutná 1 , Erik Dorko 1 , Kvetoslava Rimárová 1 , Marianna Kizeková 2 1 Department of Public Health and Hygiene, Faculty of Medicine, P. J. Šafárik University, Košice, Slovak Republic 2 Department of Occupational Medicine and Clinical Toxicology, Faculty of Medicine, P. J. Šafárik University and L. Pasteur University Hospital, Košice, Slovak Republic INTRODUCTION Zoonoses are communicable diseases transmitted from ani- mals to humans. More than 60% of human infectious diseases are caused by pathogens shared with wild or domestic animals. Emerging zoonoses are a growing threat to global health (1). Lyme borreliosis (LB) is the most prevalent tick-borne zoo- nosis in the northern hemisphere including Slovakia. It is caused by spirochetes belonging to the Borrelia burgdorferi (B.b.) sensu lato (s.l.) complex which are transmitted by ticks (2, 3). B. afzelii and B. garinii are the most common European circulating genospecies (4). From the epidemiological reports of the Specialized State Health Institute in Banská Bystrica, it appears that the number of patients with LB in Slovakia has increased from 59 cases recorded in 1986 to 1,054 cases in 2010 (incidence 19.43/100,000). In the year 2011, 852 cases were reported (incidence 15.68/100,000) and in 2012, 754 cases (incidence 13.95/100,000) (5). In the Czech Republic, the reported average incidence per year was 40/100,000 (6). The routine diagnosis of borreliosis in humans is based on the determination of the levels of specific antibodies with using the enzyme-linked immunosorbent assay (ELISA). If the first step is reactive, the immunoblotting is performed to confirm it. IgG antibodies appear in serum 6 weeks after the infection, they reach their peak level after 4 to 6 months and are detectable in serum for many years (7). Tularaemia (TUL), also known as “rabbit fever”, is a zoonosis caused by a gram-negative bacterium Francisella (F.) tularensis. TUL is typically found in animals, especially rodents, rabbits, and hares, it is usually a rural disease. F. tularensis is divided into four subspecies: tularensis, mediasiatica, holarctica, and novicida. The bacterium can be transmitted by an arthropod bite, ingestion, inhalation, or direct contact with infected tissues (8, 9). TUL was reported from many countries of northern hemi- sphere. In the Slovak Republic within the period of 1997–2008, the reported average incidence was 0.71/100,000 (8). In 2011, only 5 cases (0.10/100,000) and in 2012, 8 cases of tularaemia (0.15/100,000) were reported in the Slovak Republic (5). In the Czech Republic, the average incidence per year is similar in the range of 0.5–1.0/100,000 (6). The screening assay ELISA and then the Western blot (WB) have been established in recent years for the identification of tularaemia antibodies. Antibodies appear around 2 to 3 weeks after infection and antibodies may be detected years after the patient’s cure (9).