EN
The observations were led for 5 consecutive years (1958-1962). The total number of cases included 39.692 subjects, hospitalized, unselected from the point of view of trichomonal infestation, at the age ranging from 3 months to 90 years (19.381 women and 20.311 men). The examined represented an average population. The urinary sediment was examined in direct preparations, in the filed of vision, as well as in phase microscope. Seasonal variations were found to occur in the whole population, the most pronouncedly in women at the age of sexual activity. During the 5-year observation period the minimal infestation rate occurred in the time from December to February, the maximal one from August to November. The results were subjected to statistical analysis; the differences amount to 200-400%. The results obtained point to the existence of season-conditioned trichomonadosis. No correlation could be found between the seasonal variations and annual oscillations of temperature. It is to be assumed that in the winter time a part of infestations is latent or undergoes a spontaneous regression. Regardless of their reason, the seasonal variations should be taken into account when comparing the results of scientific investigations.