The emergence of Mycobacterium ulcerans infection near Melbourne

Objective: To document the emergence of new foci of Mycobacterium ulcerans infection (Bairnsdale ulcer) in Victoria. Methods: From data kept by one of us (JAH) and records from the Mycobacterium Reference Laboratory, Fairfield Hospital, we reviewed cases of M. ulcerans infection in Victoria between 1980 and 1995, and identified those apparently acquired outside the east Gippsland endemic region. A case was defined as a person with a lesion suggestive of M. ulcerans infection, from which the organism had been cultured or, in the absence of culture information, from which a histological specimen characteristic of M. ulcerans infection had been obtained. Results: We identified 45 people who appeared to have acquired their infections in Victoria but outside the east Gippsland region. A new focus appeared on the northern shores of Western Port, near Melbourne, in 1982, and there was a dramatic increase in cases between 1991 and 1994 associated with foci on Phillip Island, and in the Frankston-Langwarrin area of outer suburban Melbourne. Single cases came from Crib Point, Narre Warren and Bendigo. Conclusions: There have been at least three new fool of M. ulcerans infection within 80 km of Melbourne since 1982. Victorian clinicians should consider the possibility of Bairnsdale ulcer when dealing with unusual skin lesions.