Everyday contact of the workers of Białowieza sanctuary with animals may create a risk of infection by microorganisms attacking animals. The reported study was undertaken for carrying out an epidemiological analysis of tularemia and toxocarosis in this group of workers. Tularaemia infection was not found in then. In 12% of these workers antibodies to Toxocara canis were found, and fire workers had articular borreliosis. Antibodies to taxocara were disclosed in 10% of the Białowieza population not employed in the sanctuary and 30% of the population of the village Kruklanka in the Pisz Forests. The workers of the Białowieza Sanctuary are not exposed to Toxocara canis infection more than the remaining population of Białowieza and the population in the Kruklanka village in a region far from Białowieza.