Tuberculosis among health care workers during three recent decades

Some studies have found that health care workers have an increased risk of tuberculosis, whereas other studies have reported the opposite. This study examined data of Finnish health care workers (HCWs) for the incidence of tuberculosis disease. Cases of occupational tuberculosis in Finland were analysed over a period of 30 yrs (1966-1995). Control subjects were all other incident tuberculosis cases at working age. The material thus obtained included 658 people with notified occupational tuberculosis, and 56,146 control cases. The authors studied incidence, and age specific rate, as well as their trends. The incidence of tuberculosis among health care workers decreased from 57.9 to 6.1 per 100,000 and the corresponding figures among control subjects decreased from 156.8 to 9.1 per 100,000. The overall risk in health care workers was lower than in the general population throughout the study period. Analysis of age specific rates revealed no age group at increased risk. The reasons are multifactorial, among them the successful tuberculosis programme, and the lack of impact of such risk factors as immigration, human immunodeficiency virus infection and drug resistance; high coverage of bacille Calmette-Guerin vaccination may also be a factor, although it is difficult to assess.