ABSTRACT
Melioidosis is being increasingly recognized as an important cause of severe, acute community-acquired pneumonia in various tropical regions. The chronic form of melioidosis can also mimic tuberculosis. Studies have established that, while uncommon in the Port Moresby region, melioidosis is an important cause of pneumonia and sepsis in the Balimo region of Western Province. Phylogenetic analyses of strains of Burkholderia pseudomallei from Papua New Guinea have shown them to be more closely related to strains of B. pseudomallei from Australia than to strains from Southeast Asia. This is consistent with the proposed origins of B. pseudomallei in Australia, with subsequent spread out of Australia to Southeast Asia during the last ice age. Further surveillance across Papua New Guinea is likely to unmask other locations where B. pseudomallei occurs in the environment and where melioidosis is currently not being diagnosed.