Heterogeneity of Mycobacterium tuberculosis isolates in Sunamganj District, Bangladesh.

A total of 111 Mycobacterium tuberculosis isolates from new pulmonary tuberculosis patients, living in the rural Sunamganj district in northern Bangladesh were characterized with IS6110 restriction fragment length polymorphism analyses and spoligotyping. Only 3 of the isolates belonged to the W-Beijing genotype of M. tuberculosis. A high degree of diversity indicated that the spread of M. tuberculosis, in this rural area, was not caused by closely related genotypes. The tuberculosis cases in the current study were less likely to represent recent transmission than what is commonly observed in urban parts of south-east Asia. It was indicated that the tuberculosis cases of this isolated area, of a high-incidence country, represented those of an established epidemic, not yet influenced by recently disseminated strains.