The environmental microbiology of melioidosis

Melioidosis is an unusual bacterial infection. While on the one hand melioi dosis can present as an acute, rapidly fatal septicaemia, the causative age nt, Burkholderia pseudomallei, can also cause localised soft tissue infecti on or seroconversion without clinically evident infection. Distinctive epid emiological features of melioidosis include a high prevalence in southeast Asia and northern Australia, a predilection for those with prior co-morbidi ties such as diabetes mellitus, and an association with soil or surface wat er exposure. Melioidosis is also notable for primary infection or secondary recurrence after an interval of many years. The ability of B, pseudomallei to survive in soil or water for prolonged periods may explain the relevanc e of soil or water exposure to melioidosis. However, the means of transmiss ion, definitive reservoir, principal means of exposure and mechanisms of pa thogenesis have yet to be fully understood. Careful attention to the enviro nmental microbiology of B. pseudomallei will provide important insights int o the normal behaviour of this species and help to explain the environmenta l origins of melioidosis. (C) 2001 Lippincott Williams & Wilkins.