Burkholderia pseudomallei, the etiologic agent of melioidosis, is a bacterium found in soil and surface water throughout the main endemic area of Southeast Asia and northern Australia.1 It can cause acute septicemia, mild or asymptomatic, subacute, and chronic disease in humans. Risk factors such as diabetes mellitus, chronic renal failure, alcoholism, and steroid therapy have been recognized. Cases have mainly been described in mammals. There have been two reports in the literature of cases in psittaciformes.2,3 Both occurred in Australia. This is a description of nine cases of melioidosis in psittacines at a zoologic facility in Hong Kong.
The nine cases occurred between August 1996 and September 2000. Three male and six females, 2–25 years of age were affected. Cases were found dead or presented with anorexia and lethargy followed by death within 24 hours. Gross lesions at necropsy predominantly showed multifocal miliary abscesses throughout the liver and spleen as well as enlargement of these two organs. A definitive diagnosis was obtained by isolation of the gram-negative organism Burkholderia pseudomallei from multiple organs including blood. Histopathology revealed that acute septicemia was the main presentation in this case series. One bird presented with gross and histologic lesions of chronic active pericarditis.
Melioidosis should be considered as a differential diagnosis in psittacine patients in endemic areas or if imported from these areas. The veterinarian should take precautions to avoid infection during necropsy. Carcasses of birds which die of this disease should be disposed of in such manner to prevent a potential public health risk through dissemination of Burkholderia pseudomallei into the environment.
The authors wish to thank Ocean Park veterinary and laboratory staff as well as aviary keepers for their help.
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