Today in Morbidity and Mortality Weekly Report (MMWR), a new study notes that Legionella bacteria likely spread from donated organs to two lung transplant recipients, marking the first time transplanted organs have been the likely source of infection.
Elsewhere, the World Health Organization (WHO) reported that, as of September 11, a total of 166 cases of legionellosis, including 23 deaths, have been reported in Poland.
Both studies highlight the continued threat Legionella bacteria pose.
In MMWR, authors report that in July 2022, the Pennsylvania Department of Health received two reports of laboratory-confirmed Legionnaires disease in patients who had recently received lung transplants from the same donor at a single Pennsylvania hospital. The donor drowned after being submerged in a river for at least 5 minutes. Legionella bacteria naturally live in fresh water.
"Organ recovery occurred within 7 days of the drowning event. At the time, exposure to Legionella was not suspected, and no testing for Legionella was performed on any donor specimens before or after organ recovery," the authors wrote.
Freshwater source likely
The recipients of the donor’s lungs included a woman aged 70 to 79 years and a man in his 60s. Postoperative complications appeared for both patients in the week after transplant, but diagnosis took several weeks. Once diagnosed with legionellosis, both patients were treated with doxycycline. The patients had different Legionella species, but the authors said this could be explained by the river water source.
Patient A, the woman, fully recovered. Patient B, the man, died within 6 months of his transplant due to respiratory failure secondary to a mucous plug, the authors said.
Clinicians caring for patients who receive organs from donors who experienced freshwater drowning also should maintain a higher index of suspicion for legionellosis.
The initial organ donor also donated a heart, liver, and right kidney to three other recipients. No legionellosis was reported in those recipients. No other patients seen at the Pennsylvania hospital reported legionellosis, which means the bacteria was likely not spread from building water sources, including cooling towers.
"The present findings suggest that clinicians caring for patients who receive organs from donors who experienced freshwater drowning also should maintain a higher index of suspicion for legionellosis, even in organ recipients without classic clinical symptoms," the authors concluded. "In such patients, posttransplant antimicrobials could be tailored to include agents that combat atypical waterborne organisms."
Polish cases concentrated in Rzeszow
In Poland, recent months have brought a swift uptick in legionellosis cases, according to the WHO, with a current case-fatality rate of 14%.
This observed increase in confirmed cases, and associated hospitalizations and deaths seen since mid-August, is unusual.
"This observed increase in confirmed cases, and associated hospitalizations and deaths seen since mid-August, is unusual, considering that the number of cases is higher than the annual number reported in Poland since 2016," the WHO wrote. Most cases (112 [67%]) were recorded in the city of Rzeszow, 23% (38) of cases in Rzeszow County, and 10% (16) cases in other locations.
Extensive mapping and sampling has been taken of the city’s water supply system, residences of the sick, healthcare facilities, and cooling towers, but no source has been established. Public fountains, public water sprays, and other public water sources have been shut down temporarily, the WHO said.