The present paper analyzes immunological parameters and the incidence of secondary immunodeficiency (SID) in physicians and medium-levelled medical staff contacting with tuberculous and non-specific infection. Suppressed cell immunity was recorded in 44% of the medical staff of a pulmonary surgical tuberculosis hospital, with increased length of service there was a rise in the number of patients diagnosed as having immunodepression. The clinical manifestations of SID were recorded in 56% in this group and they were most pronounced in a group of long-working personnel. The proportion of persons with immunodepression proved to be twice higher among nurses than among physicians. Nurses are at the highest risk for immunopathological states. This common occurrence of SID among medical staff is an indicator to make an obligatory regular immunological examinations of the staff for the prevention and immunotherapy of SID.