Background: The objective of the study was to collect the data on undetected hepatitis C virus (HCV) in the frequently hospitalized residents of the Kujawsko-Pomorskie Voivodeship. Material and Methods: The analysis focused on empirical data. The research was conducted in 2013 among 6332 citizens of the Kujawsko-Pomorskie Voivodeship who had been hospitalized at least twice. The blood was tested for the presence of anti-HCV antibodies. The diagnostic survey with an anonymous questionnaire was developed and used for the purpose of the study. For the statistical analysis Statistica 10.0 was used. The hypothesis was verified using the Mann- -Whitney U test and Chi² test of independence. A level of statistical significance was assumed at α = 0.05. The results were considered to be statistically significant if the probability fulfilled the inequality of p < 0.05. Results: Positive anti-HCV antigens were detected in 91 (1.44%) examined individuals. The relationship was found between blood transfusions provided before 1992, the use of intravenous narcotics and doping, and minor surgical procedures and the infection. Conclusions: Asymptomatic infection was detected in 91 citizens of the Kujawsko-Pomorskie Voivodeship. The highest risk of HCV infection occurs during small surgery and usage of intravenous narcotics and doping. The percentage of positive results is slightly higher in the group of people with cosmetic and beauty treatments. Planning screening programs special attention should be paid to this group of risk. Blood and blood products transfusions before 1992 were associated with a higher risk of HCV infection. People with above-mentioned interventions should become a particular group of screening program participants. Occupational medicine service plays an important role in prevention. Med Pr 2014;65(5):633–637