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NOTE: A surveillance case definition is a set of uniform criteria used to define a disease for public health surveillance. Surveillance case definitions enable public health officials to classify and count cases consistently across reporting jurisdictions. Surveillance case definitions are not intended to be used by healthcare providers for making a clinical diagnosis or determining how to meet an individual patient’s health needs.

Clinical Description

Clinical presentation of the disease varies on a case by case basis. The following characteristics are typical of melioidosis.

  • An acute or chronic localized infection which may or may not include symptoms of fever and muscle aches. Such infection often results in ulcer, nodule, or skin abscess.
  • An acute pulmonary infection with symptoms of high fever, headache, chest pain, anorexia, and general muscle soreness.
  • A bloodstream infection with symptoms of fever, headache, respiratory distress, abdominal discomfort, joint pain, muscle tenderness, and/or disorientation.
  • A disseminated infection with symptoms of fever, weight loss, stomach or chest pain, muscle or joint pain, and/or headache or seizure. Abscesses in the liver, lung, spleen, and prostate are often observed in patients diagnosed with disseminated infections; less frequently, brain abscesses may be seen.

Laboratory Criteria For Diagnosis

Confirmed cases:

  • Isolation of B. pseudomallei from a clinical specimen of a case of severe febrile illness: Culture of the organism may be done by blood, sputum, urine, pus, throat swab, or swabs from organ abscesses or wounds.


  • Evidence of a fourfold or greater rise in B. pseudomallei antibody titer by IHA between acute- and convalescent-phase serum specimens obtained greater than or equal to 2 weeks apart.
  • Evidence of B. pseudomallei DNA (for example, by LRN-validated polymerase chain reaction) in a clinical specimens collected from a normally sterile site (blood) or lesion of other affected tissue (abscesses, wound).

Case Classification


A case that meets the clinical case definition, one or more of the probable lab criteria, and one of the following epidemiologic findings:

  • History of travel to a melioidosis-endemic region, OR
  • Known exposure to B. pseudomallei as a result of intentional release or occupational risk (lab exposure).


A case that is laboratory confirmed, with or without clinical evidence.


States and territories should also notify the CDC’s Bacterial Special Pathogens Branch of such cases by calling 404-639-1711 or emailing:

Related Case Definition(s)