A potentially deadly type of bacterium previously found only in parts of Southern Asia, Africa or Australia has been detected for the first time in soil and water samples in the U.S., the Centers for Disease Control and Prevention said Wednesday.
The bacterium, Burkholderia pseudomallei, can cause an illness called melioidosis, which has proven fatal in half of cases worldwide.
About a dozen cases are discovered every year in the U.S., usually among people who had traveled overseas.
On Wednesday, however, the CDC announced that the bacterium had been found in soil and water samples along the Gulf Coast of Mississippi, and it issued a health alert to physicians nationwide to be on the lookout for symptoms of melioidosis, which can be vague, including cough, fever and chest pain. In more severe cases, the illness can lead to disorientation, pneumonialike illness and seizures.
"It is unclear how long the bacteria has been in the environment and where else it might be found in the U.S.," the CDC said in a statement.
Dr. Jill Weatherhead, an assistant professor of tropical medicine and infectious diseases at the Baylor College of Medicine in Houston, was not surprised that the bacterium had made its way into the country.
"We live in a subtropical climate here in the U.S. along the Gulf Coast, where it's warm and humid. This is a suitable environment for Burkholderia pseudomallei," she said.
The bacterium has the potential to thrive anywhere along the Gulf Coast, she said, and it could become endemic.
The discovery of the bacterium in U.S. soil comes after two people who were not related but lived near each other in Mississippi became sick with melioidosis — one in 2020 and the other in 2022.
According to the CDC's health alert for doctors, both patients were hospitalized with sepsis after they developed pneumonia. Both were given antibiotics and recovered.
Samples taken from the soil and puddles near the patients' homes contained the bacterium, confirming its presence in the U.S., the CDC said.
The same bacterium was also found last year in contaminated aromatherapy room spray that sickened four people in Georgia, Kansas, Minnesota and Texas. The cases were unrelated to the current alert, as the spray had been imported from India, where B. pseudomallei is endemic.
Two of those people, including a 5-year-old boy, died. The two other patients were left with lasting physical and mental health problems.
Walmart, which sold the imported product, recalled nearly 4,000 bottles of its Better Homes & Gardens Lavender & Chamomile Essential Oil Infused Aromatherapy Room Spray with Gemstone.
Although B. pseudomallei has now been found in U.S. soil and water, infectious disease experts say it's unlikely the bacterium will cause widespread harm.
"It takes a significant exposure," either through an open sore or ingestion, to cause illness in people, said Dr. Chris Woods, a professor of medicine at the Duke Global Health Institute.
Usually, he said, that occurs in places where the bacterium has grown and become concentrated.
While melioidosis is treatable with certain intravenous antibiotics, doctors say it can be difficult to make a correct diagnosis in time to help patients.
The CDC said that people living along the Gulf Coast may want to take extra precautions when they are in contact with soil or muddy water, such as wearing waterproof boots and covering open wounds.