IS6110 restriction fragment length polymorphism of Mycobacterium tuberculosis isolates from an area of Casablanca, Morocco.

Using IS6110 RFLP, 61 isolates recovered from new cases of pulmonary tuberculosis (TB) were compared from September to December 1999 in Casablanca, Morocco, a city with a high incidence of TB. The majority of the isolates (92%) harboured 6-14 copies of IS6110. The minimal fraction of patients in groups of recently acquired infection is 13.1%. This preliminary study showed that IS6110 RFLP is a suitable method for finger-printing Mycobacterium tuberculosis in Casablanca. The unexpectedly low level of recent transmission of TB found in this study deserves further studies involving higher numbers of isolates recovered during a longer recruitment period.