麻豆传媒

The CDC has detected Burkholderia pseudomallei -- a bacteria that can cause the rare and sometimes deadly melioidosis disease -- in environmental samples along the Gulf Coast region.

This marks the first time B. pseudomallei has been found on U.S. soil, but it's likely the bacteria has been present since at least 2020, and modeling data suggest the area is well-suited for continued growth, the agency warned. Once well-established in soil, the bacteria cannot feasibly be removed.

In a on Wednesday, the CDC said B. pseudomallei was "locally endemic" along the Mississippi Gulf Coast after being identified in soil and water sampling, and is alerting clinicians in the region to watch for signs and symptoms of melioidosis disease in their patients. The disease should also be considered in patients with a who recently traveled to the area as well.

"Patients generally present with acute illness, but about 9% present with chronic infection, with symptoms lasting over two months," and "chronic melioidosis cases often mimic tuberculosis clinically," according to the agency.

CDC detailed how in 2020 and 2022, two unrelated U.S. individuals from the Gulf Coast both became sick with melioidosis, prompting disease detectives to sample the surrounding soil and water, along with household products. Three environmental samples taken from soil and puddle water this year tested positive for B. pseudomallei, the CDC said, and sequencing data revealed that both patients were infected by the same novel strain of the bacteria.

"Melioidosis has a wide range of nonspecific symptoms like fever, joint pain, and headaches and can cause conditions that include pneumonia, abscess formation, or blood infections," the agency noted in "B. pseudomallei has historically been found in tropical and sub-tropical areas such as South and Southeast Asia, northern Australia, and parts of Central and South America and Puerto Rico."

Worldwide, case fatality rates with the disease range from 10% to 50%, but cases have been too few in the U.S. (about a dozen per year) for accurate numbers.

If a patient is diagnosed with melioidosis, CDC strongly recommends that physicians consult with an infectious disease specialist, and treatment consists of intravenous antibiotics for a minimum of 2 weeks (and up to 8 weeks depending on response). To prevent relapse, oral trimethoprim-sulfamethoxazole is recommended, or amoxicillin/clavulanic acid if patients cannot receive trimethoprim-sulfamethoxazole.

Four widely reported cases of melioidosis in 2021 -- in Georgia, Kansas, Minnesota, and Texas -- were linked to a contaminated imported aromatherapy spray sold at Walmart, but Alfredo Torres, PhD, MS, of the University of Texas Medical Branch in Galveston, said the 2020/2022 cases detailed by CDC on Wednesday appear unrelated.

He noted that a predicted that southern parts of the U.S. -- including Florida, Mississippi, Alabama, etc. -- would be able to sustain B. pseudomallei in the soil.

"It is quite possible that climate changes are letting the pathogen [find] a new niche for survival in the soil and instead of being deep down from the surface, the pathogen is now on the surface and individuals can get infected with it," he told 麻豆传媒 by email.

The CDC said people living along the Gulf Coast of Mississippi with health conditions placing them at high risk for poor outcomes from melioidosis -- e.g., heavy drinkers, people with diabetes or chronic kidney disease or lung disease -- should take precautions, such as avoiding contact with soil or muddy water, especially after heavy rains.

In general, CDC said the risk to the general public was low, but that it would continue monitoring for environmental spread and noted that as a nationally notifiable disease, melioidosis disease should always be reported to state health departments.

Kristina Fiore contributed reporting to this story.

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