[Occupational exposure to multiresistant Mycobacterium bovis in a hospital in Saragossa, Spain]

Those working in a hospital environment are exposed to different occupational risks, although more specifically biological ones. One of the major risks is that of exposure by airborne transmission, more specifically, tuberculosis. This study is aimed at providing a description and analysis of the results of the implementation of an evaluation and surveillance protocol following occupational exposure to Multiresistant mycobacterium bovis (MRMb).

A male patient was diagnosed with MRMb infection at the Miguel Servet Hospital in Zaragoza in 1999 following ten days without respiratory isolation. During this period, he came into contact with 167 employees from different hospital departments. A surveillance and contact control protocol was prepared based on: completing a survey and undergoing an initial Mantoux (if the employee had previously tested negative for tuberculin), followed three months later by a chest X-ray and then a two-year clinical follow-up (check-ups every three months) for those having tested positive for tuberculin and no administering of chemoprophylaxis even though signs of infection were to have been found.

Information was gathered on 160 employees (96%). A total of 94 employees (59%) had previously undergone a Mantoux, seven (7) having had tuberculosis. It was necessary for a follow-up to be conducted on sixty-one (61) employees who tested positive (29 previously positive and 32 detected in the initial Mantoux). No employee who had tested negative on an initial Mantoux tested positive on repeated testing three months later nor showed any symptoms indicative of transmission during the follow-up period. Some variables, such as age or working in the Infectious Disease Unit were related, on a statistically significant basis, to follow-up being required.

The risk of occupational transmission following contact with MRMb might be similar to M. Tuberculosis, although further experience would be required in order to confirm this fact. Early diagnosis and availing of a protocol for implementing measures aimed at preventing and controlling this type of occupational exposure are of importance.