Tuberculosis as an occupational hazard for health care workers in Estonia

Tuberculosis incidence has been increasing in the Baltic states since the 1990s, accompanied by the emergence of drug resistance, including multidrug resistance (MDR). In this changing situation, the potential threat of nosocomial spread of tuberculosis to other patients and health care workers (HCW) has remained unrecognised.

To investigate the risk of tuberculosis in health care workers in Estonia.

Cases of tuberculosis registered among HCWs from 1994 to 1998 were evaluated. The case records were analysed retrospectively and combined with bacteriological data including data on drug resistance.

Sixty-seven HCWs (23 physicians, 23 nurses and seven laboratory technicians, 12 assistant nurses and two cleaners), all of whom tested negative for human immunodeficiency virus, were diagnosed as having active tuberculosis. The incidence of tuberculosis among HCWs (mean 91/100,000/year) was 1.5 to three times higher than in the general population. In a chest hospital in charge of regional tuberculosis care, the incidence was 30 to 90 times higher, and was highest among physicians. In 49 HCWs tuberculosis was confirmed by culture. Among these, drug resistance was detected in 23 (49%), 18 (38%) of whom had MDR tuberculosis.

Health care workers, especially those working in a chest hospital where tuberculosis patients were treated, were found to be at an elevated risk of tuberculosis. MDR tuberculosis poses a particular threat which is difficult to combat.