Epidemiology and molecular typing of an outbreak of tuberculosis in a hostel for homeless men

Aim-To investigate a possible outbreak of tuberculosis in a hostel for home less men using IS6110 profiling, a polymerase chain reaction (PCR) based fi ngerprinting technique. Methods-Eight cases of tuberculosis were diagnosed in residents of the host el over a period of 28 months. To provide epidemiological data, a hemineste d inverse PCR (HIP) assay targeting the insertion sequence IS6110 together with its upstream flanking region was used to fingerprint the eight isolate s of XI tuberculosis under investigation. Results-The HIP technique gave IS6110 profiles which showed that while thre e isolates were clearly distinct, the remaining five strains were indisting uishable, suggesting the latter were representatives of a single outbreak s train. Conclusions-The HIP assay proved discriminatory and facilitated repeated te sting for the direct comparison of strains as more patients presented over the protracted course of this outbreak.