Nosocomial Transmission of Multidrug-Resistant Mycobacterium tuberculosis in Spain

Before 1990, outbreaks of multidrug-resistanttuberculosis (MDRTB) were uncommon (1); sincethen, more than 10 outbreaks have been reported,all in hospitals and prisons in the eastern UnitedStates (2-7). Persons traditionally considered atrisk for MDRTB (foreign-born TB patients andthose inadequately treated for TB) have not beenassociated with these outbreaks. Instead, the pres-ence of patients with active TB near immunocom-promised patients in HIV-dedicated wards has ledto MDRTB-infected HIV patients whose TB casesoften go unrecognized. The patients receive inade-quate treatment in facilities without effective pro-cedures for isolating acid-fast bacilli; thesecircumstances favor nosocomial transmission.Health officials in other geographic areas whereHIV and TB are major public health threats havebeen alerted to this emerging problem, and sur-veillance systems have been designed (8).