By Crystal Phend

While the lavender-scented spritz from Walmart might have seemed the furthest thing from exotic, the Burkholderia pseudomallei bacteria inside sparked a deadly melioidosis outbreak that CDC scientists highlighted as a reason to watch for unexpected infections.

"Health care providers should consider melioidosis in patients with a compatible illness, even if they do not have a history of travel to melioidosis-endemic areas," Jay E. Gee, PhD, of the CDC's Bacterial Special Pathogens Branch in Atlanta, and colleagues reported.

The bacterium, typically associated with travel to tropical and subtropical areas like Thailand and Malaysia, where it's endemic in soil and water, was a mystery when it showed up in four patients in Georgia, Kansas, Minnesota, and Texas in 2021.

None of the four (two children ages 4 and 5, two adults both age 53) were related or had such a travel history, perhaps not surprising during the pandemic.

Initial presentation ranged from cough and shortness of breath, to weakness, fatigue, nausea, vomiting, intermittent fever, and rash on the trunk, abdomen, and face, later diagnosed as meningoencephalitis.

The CDC knew there was a potentially common source of exposure based on genomic analysis of the initial case, a woman who showed up in the emergency department on March 13, 2021, with cough, shortness of breath, malaise, and weakness. She had a number of comorbid conditions, notably chronic obstructive pulmonary disease (COPD), cirrhosis from hepatitis C, substance abuse, and psoriatic arthritis.

After starting on empirical antibiotics for community-acquired pneumonia and a urinary tract infection, she got glucocorticoids for COPD exacerbation. Her condition deteriorated despite escalating antibiotics over the next several days and she died in the ICU on day 9.

The next two cases occurred in May 2021.

A 4-year-old girl from Texas with fever initially diagnosed as viral gastroenteritis, and then urinary tract infection, ended up in the ICU with septic shock and meningoencephalitis. She got antibiotics and methylprednisolone as well but respiratory and neurologic status continued to decline until her lower respiratory culture pointed to burkholderia bacteria. IV meropenem, ceftazidime, and trimethoprim-sulfamethoxazole worked but she remained nonverbal and dependent on a wheelchair at 3 months post-discharge.

A Minnesota man sent to the emergency department with altered mental status and weakness was initially diagnosed with acute metabolic encephalopathy and mild degeneration of his hip. When he returned with fever and respiratory problems, he was treated for pneumonia and acute inflammation in his hip. Culture of the joint aspirate turned up burkholderia bacteria. Despite antibiotic treatment, his mental status didn't recover and his hip joint had evidence of osteonecrosis.

The CDC had been working with state health departments to try to figure out what was going on but there were no clues from the many household cleaners and personal care products examined as potential sources of infection, as had been reported last fall after the initial CDC description of the cases.

It was the fourth case that cracked it: a 5-year-old boy in Georgia who came to the emergency department with fever, weakness, tongue swelling, sore throat, nausea, and vomiting. He developed respiratory problems after admission and was treated for presumptive COVID-19 and possible superimposed bacterial infection. After 4 days, he was discovered to have had a large cerebral infarct and died that day. Autopsy turned up disseminated melioidosis with B. pseudomallei in the lungs, liver, and brain as well as SARS-CoV-2.

"They had tested several hundred specimens and it looked like it was coming to a dead end," CDC epidemiologist Jennifer McQuiston, DVM. But when the team tried a second, last-ditch search at the boy's home, "they collected a specimen from an air freshener bottle that had not been collected the first time around."

Bingo.

Better Homes & Gardens' "Lavender & Chamomile with Gemstones" essential oil room spray imported from India (now under recall) was found in all four cases and all carried the same B. pseudomallei strain, dubbed ATS2021 for "aromatherapy spray 2021."

Gee's group noted that there have been other melioidosis cases in the U.S. in recent years, and not just related to travel. A 2019 case came from the patient's aquarium; others have come from contaminated wound-irrigation fluids and hand cleaners. Some reports suggest that B. pseudomallei could be endemic in the southern U.S.

"Melioidosis is an emerging infectious disease in the United States," Gee and colleagues concluded.

In addition to considering it in patients with compatible illness, regardless of travel history, they suggested that "patients who have acute respiratory or neurologic symptoms that do not have a response to initial treatment may be candidates for closer assessment for melioidosis."

The specimens to culture should be guided by the clinical syndrome, whether blood, sputum, urine, joint aspirate, or cerebrospinal fluid. However, the laboratory should be informed if melioidosis is suspected so that staff can protect themselves from exposure, as some procedures may aerosolize particles.

Also, two of the cases were initially misdiagnosed as a different burkholderia species using MALDI-TOF mass spectrometry or Vitek 2 instrument gene sequencing.

"Health care providers are encouraged to reevaluate patients with isolates identified by automated systems as burkholderia species (specifically B. cepacia and B. thailandensis), Chromobacterium violaceum, Ochrobactrum anthropi, and possibly aeromonas species, acinetobacter species, and pseudomonas species in order to assess for possible infection with B. pseudomallei," Gee's group cautioned.

And of course, report it to public health officials if found, they added.