[Discussion on incidence of tuberculosis patients among nurses in Osaka City]

To analyze conditions of developing TB among nurses and to discuss preventive measures.

TB patient cards of nurses and other health workers registered in Osaka City from 1999 to 2003 were studied.

Incidence rate of TB among female nurse/ assistant-nurse was 3.0 times higher than that of all female population. The route of case finding were as follows with descending order, visit to medical facilities with symptoms (55.8%), regular health check (35.8%), individual health check (5.8%), and contact examination (2.5%). Among risk factors related to the development of TB work in hospitals account for 55.0% in nurse patients of all ages, 72.5% in 20s, 47.4% in 30s, 37.5% in 40s, 36.4% in 50s and 0% in 60s. Individual risk factors were identified as follows in descending order, "TB patients diagnosed in the hospital." (10.0%), "examined at TB contact examination." (9.2%), "history of TB treatment at 18 years of age and over" (7.5%), "working experience in TB hospital/TB ward." (6.7%), "TB patients diagnosed among colleague." (5.0%), "increased reaction of tuberculin skin test after employment." (2.5%), "diagnosis of 'healed TB lesion" at regular health check." (1.7%), "default of chemoprophylaxis" (1.7%). Among various risk factors, "examined at TB contact examination" and "TB patients diagnosed in the hospital" are the two most common factors and occupied 38.8% in patients in 20s.

Therefore it is important to promote further nosocomial TB infection control with a view to lower incidence rate of TB among nurses, which is 3 times higher than that of all female population.