What the CDC Knows About U.S. Melioidosis Cases After Rare Tropical Disease Kills Two

On August 9, the Centers for Disease Control and Prevention (CDC) issued a statement announcing that there had been a new, fatal case of a rare and serious tropical disease known as melioidosis in the United States.

The CDC said the fatal case, which occurred in Georgia, was linked to three other previous cases that were identified in Kansas, Texas and Minnesota. One of these three additional cases also died.

Dr. Maria Negron, a melioidosis expert from the CDC, told Newsweek that the agency has been working with the departments of health in the four states where the recent cases occurred in order to find out more about them.

Melioidosis is an infectious disease caused by the bacteria Burkholderia pseudomallei, which is endemic to tropical and subtropical climates—particularly Southeast Asia and northern Australia.

The bacteria can be found in contaminated water and soil, but it has also been documented in wet or moist products in areas where it is prevalent.

The CDC said it thinks that the most likely source of the infections was an imported product—such as a food, drink, personal care or cleaning product, or a medicine—given that none of the individuals had traveled abroad.

"Most people who are diagnosed with melioidosis in the United States had traveled to areas where the bacteria naturally occurs and the strains from these cases typically match the patient's travel history," Negron told Newsweek.

"The fact that these patients did not travel internationally, and the bacterial strains closely match each other and resemble strains from South Asia suggests to us that the cause of the infections are likely exposures to an imported product from this region."

Negron said the agency was testing samples collected from in and around the homes of the four cases, including products they commonly used.

"We are comparing products typically used in these households to try to identify products used in common among the patients," Negron said. "To date, a common product has not been identified to link the four cases."

"We are also reviewing potential melioidosis cases submitted by state health departments from around the country to see if any are related to the outbreak strain. Currently, we have not identified any new cases."

According to the expert, the four cases do not have a particular pattern. They have occurred among children and adults, while only two of the individuals had risk factors that made them more likely to get sick.

The CDC is recommending that clinicians consider a melioidosis diagnosis even if the patient has not traveled recently to regions where the Burkholderia pseudomallei bacteria naturally occurs, and does not have any of the typical underlying medical conditions that place them at greater risk.

The agency is currently working with state and federal health authorities to try and learn what products the four cases may have been exposed to and whether they were manufactured outside the United States—potentially in Asia.

"It's also possible it could be an ingredient in a product, which makes solving the puzzle that much more difficult," Negron said.

"The best thing that people can do is to be aware of their health. If they begin to have symptoms of melioidosis, we recommend that they see a health care provider and be sure to ask if it could be melioidosis. In many cases, early identification and treatment of infections is key to preventing more severe illness."

While the CDC is trying to raise awareness of the disease in the U.S., Negron said the chance of getting sick with this bacteria in the country is "extremely low."

Only around a dozen melioidosis cases are identified every year in the United States, most of whom have traveled from regions were the bacteria is endemic, according to the CDC.

It is also important to note that exposure to this bacteria doesn't necessarily result in the development of disease.

"We know from studies in areas where melioidosis is common that most people who are exposed to this bacteria do not get sick or have only a mild illness," Negron said. "We also know that people who have risk factors such as diabetes and chronic lung disease are more likely to develop disease if they are exposed to this bacteria."

"Seeking health care when showing symptoms such as shortness of breath and fever is the most important thing people can do. There is effective treatment for melioidosis, but early identification of the disease is critical."

Illustration of bacteria
An artist's illustration of bacteria. The rare disease melioidosis is caused by the bacteria Burkholderia pseudomallei. iStock