BOVINE TUBERCULOSIS IN SWEDISH DEER FARMS - EPIDEMIOLOGIC INVESTIGATIONS AND TRACING USING RESTRICTION FRAGMENT ANALYSIS

Bovine tuberculosis was eradicated from Sweden after a programme lasti ng many years, By 1991, no tuberculosis in wildlife had been discovere d for 50 years and the last case in cattle had occurred 13 years befor e, In 1991, the disease was identified in a herd of farmed fallow deer (Dama dama) and over the next three years nine other infected herds m ere identified, Investigation revealed that all the infected deer were either deer that had been imported into Sweden from the United Kingdo m in 1987 or had been in contact with them, Restriction fragment analy sis of eight isolates of Mycobacterium bovis from five of the herds sh owed that the isolates had identical patterns of DNA fragments, which indicated a common source of infection, Among more than 800 isolates o f M bovis that have been analysed, these patterns were identical to th ose of only two previous isolates, both of which came from British dee r, These results indicate that the eight Swedish strains of M bovis an d the two British strains may have a common source of infection.