What is melioidosis?: Rare tropical disease has killed 2, sickened 2 others in US

Infectious disease experts are stumped by the newest health threat menacing the United States.

Melioidosis, a rare bacterial disease typically found in tropical climates and also known as Whitmore’s disease, has infected four people in four different U.S. states in recent months, killing two of them.

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According to the U.S. Centers for Disease Control and Prevention, the infections are widespread across southeast Asia and northern Australia, and the four domestic cases appear to be the first known melioidosis diagnoses confirmed to have originated on U.S. soil because none of the four infected persons had recently traveled abroad.

The bacterium that causes melioidosis infections, Burkholderia pseudomallei, is typically found in contaminated water and soil and spreads to humans and animals through direct contact with the contaminated substances, the CDC stated.

The most recent U.S. melioidosis death occurred last month in Georgia, while one case each had already been confirmed in Kansas, Minnesota and Texas, the Deseret News reported.

Federal health officials sent an alert about the latest case to doctors Monday, asking them to consider melioidosis if they encounter antibiotic-resistant bacterial infections, even if the patient has not traveled outside of the country.

According to the CDC, the infections are treatable if caught early and treated correctly.

So how exactly did four different people of widely varying ages and health histories who never left the country contract a tropical disease?

Investigators are attempting to answer that question now and have determined through lab analyses that even though the four U.S. cases were reported in four different states at different times, the infections were closely related.

The CDC said that it believes the most likely cause is an imported product or an ingredient in an imported product, but a specific culprit has not yet been identified. Meanwhile, the incubation period, or the amount of time between exposure to the bacteria and exhibition of symptoms, is typically two to three weeks but can be as short as a few days or as long as several years, complicating contract tracing efforts.

In addition, melioidosis includes a wide range of signs and symptoms that are often mistaken for other diseases such as tuberculosis or more common forms of pneumonia, the CDC stated. In turn, the agency groups melioidosis into three primary infection categories with the following most-common symptoms:

Localized Infection

  • Localized pain or swelling
  • Fever
  • Ulceration
  • Abscess
  • Pulmonary Infection:
  • Cough
  • Chest pain
  • High fever
  • Headache
  • Anorexia

Bloodstream Infection

  • Fever
  • Headache
  • Respiratory distress
  • Abdominal discomfort
  • Joint pain
  • Disorientation

Disseminated Infection

  • Fever
  • Weight loss
  • Stomach or chest pain
  • Muscle or joint pain
  • Headache
  • Central nervous system/brain infection
  • Seizures

Meanwhile, certain underlying medical conditions may increase an individual’s likelihood of contracting melioidosis, including:

  • Diabetes
  • Liver disease
  • Renal disease
  • Thalassemia
  • Cancer or another immune-suppressing condition not related to HIV
  • Chronic lung disease, such as cystic fibrosis, chronic obstructive pulmonary disease and bronchiectasis

Click here for more from the CDC.

-- The Associated Press contributed to this report.