CDC warns of potentially deadly invasive bacteria found in southern Gulf states: What to know

This bacterium causes the illness melioidosis in humans.
This bacterium causes the illness melioidosis in humans.

Researchers have discovered a foreign microbe so deadly it's considered a bioterrorism agent growing wild in the U.S. ‒ specifically in states along the Gulf of Mexico.

That much we know for sure. Yet a person innocently Googling "Burkholderia pseudomallei," the bug's scientific name, and "Gulf of Mexico" could sure come away with the wrong impression ‒ namely that the stuff is floating around out there and anyone who swallows or even breathes it in has a 50/50 chance of dying from it.

Not so fast. Yes, the U.S. Centers for Disease Control and Prevention has warned about it. Yes, researchers have found it in Mississippi and Texas, but in fresh water and soil. Yes, they're concerned about it spreading. Yes, it can be deadly, but to immunocompromised people ‒ most healthy folks who get it shake it off without missing a beat.

There have been a lot of scary headlines leaving the impression that it might soon be killing tourists. Here's what we actually know about the bacteria.

It lives in soil and fresh water as far as we know

Contrary to reports blaming the Gulf of Mexico, the bacteria doesn't like salty water. When CDC researchers found it in Mississippi last July, "three of the samples taken from soil and puddle water in 2022 tested positive at CDC for B. pseudomallei, indicating bacteria from the environment was the likely source of infection for both individuals and has been present in the area since at least 2020," the agency reported.

In order to get it, direct contact with the bacteria is needed, which can happen by touching it with broken skin, Park says, by swallowing it, or by breathing infected droplets, as happened in 2021 when four cases in four states were linked to an imported aromatherapy spray sold in Walmarts (and since removed). Florida's sole case of the disease was in the north central part of the state in Alachua County in 2021, according to the state health department.

It's not from here

Like Burmese pythons and Brazilian peppers, it's an alien invader that was somehow imported and is now living and reproducing on its own. Primarily found in Southeast Asia and Australia, "It's from (places) where there's a tropical climate (and) now, unfortunately seems to have a home around the Gulf Coast," said epidemiologist Sarah Park, medical director of medical affairs at Karius, a California company that makes a test for the disease.

But even though CDC disease detectives found it at two Mississippi sites, "It's not clear how prevalent it is in the environment yet," said Park, who worked more than a decade as Hawaii's state epidemiologist. "But it's safe to say there are more cases … It's always concerning when you have a new organism that should be in another part of the world in yours."

The 12 or so cases diagnosed in the U.S. annually mostly occur in "people with recent travel to a country where this bacteria is endemic," the CDC says.

It can stay dormant for years

It's possible to pick the bacteria up and not develop symptoms for decades. It has been called a "time bomb" because soldiers who served in the Vietnam War became sick decades after exposure.

"In case of immunosuppression, melioidosis may be reactivated, with reports of latency periods lasting up to 26 years, as seen in US veterans returning from Vietnam," reports the Journal of Community Hospital Internal Medicine Perspectives.

It's a disease mimic

One of the reasons the CDC put out an alert about it is because the disease it causes, called melioidosis, shares symptoms with a host of other diseases. In areas like the Philippines, where it's more common, it's known as "the great mimicker."

It can look like tuberculosis, the flu, pneumonia, encephalomyelitis, septic arthritis, osteomyelitis and more. In parts of the world where it's common, the CDC says melioidosis is fatal in 10% to 50% of cases.

The diagnostic gold standard is to culture it in a lab from a swab or to have a blood test. Meanwhile, the CDC urges clinicians to "be aware of the signs and symptoms of melioidosis and to consider melioidosis in patients that present with symptoms of the disease."

Generally healthy people probably don't have to worry

It's not impossible for otherwise healthy people to get it, but underlying conditions increase the risk, the CDC says. The agency identifies the major risk factors as:

  • Diabetes

  • Liver disease

  • Renal disease

  • Thalassemia

  • Cancer, or another condition (not related to HIV) that weakens the immune system

  • Chronic lung disease (such as cystic fibrosis, chronic obstructive pulmonary disease and bronchiectasis)

"People with underlying medical issues just need to be vigilant," Park said. "Remember clinicians aren't clairvoyant, so remember to mention where you've been and what you've been doing."

Burkholderia pseudomallei bacteria grown on sheep blood agar for 72 hours.
Burkholderia pseudomallei bacteria grown on sheep blood agar for 72 hours.

This article originally appeared on USA TODAY NETWORK: What to know about deadly bacteria found in Gulf-area soil, water