An outbreak of pyomyositis in a large refugee camp in Thailand.

During a 2-month period, 17 cases of pyomyositis were seen in the hospital population of a large refugee camp for Cambodians in Thailand. The temporal clustering of the cases suggests an epidemic pattern. Patients in this series were generally young and otherwise healthy. All had gram-positive cocci demonstrated in abscess pus, and all responded to surgical drainage. Fourteen (82%) of the cases were initially misdiagnosed by volunteer physicians who were unfamiliar with the disease. The authors suggest that a mosquito-borne virus predisposes to the development of the pyomyositis abscess.