In recent years, the most cases of human trichinellosis were caused by consumption of meat of infected wild boars, hunted illegally and not investigated for presence of Trichinella spp. The growing percentage of infected wild boars poses expanding risk to humans. It has also been noticed that year by year the number of trichinellosis cases in pigs population, has increased. Especially in recent years when its prevalence in swine has become often focal. The domestic and sylvatic cycles often overlap with common vectors, such as rodents, living in the elds in summer, and gathering in farms in winter where they have free access to food. These vectors may have great importance in transmission of Trichinella between swine farms and sylvatic environment. The important role in transmission may also play farm owners, supporting parasite circulation by illegal actions (e.g. feeding pigs with wastes from hunted animals). Epidemiological investigations undertaken by veterinary services in the trichinellosis outbreaks in pig farms are compulsory step to stop further transmission of the parasite and to protect humans health. It is of particular importance in endemic regions, i.e. in the Wielkopolskie, Zachodniopomorskie, Kujawsko-Pomorskie and Pomorskie voivodships, as these are areas of highest concentration of pig production.