Two lungs transplanted in Philly were likely carrying Legionnaires’ disease, the first case of its kind

Two people who received lung transplants from the same donor at Temple University Hospital last year later developed the serious respiratory infection Legionnaires’ disease — likely from the donated lungs themselves, which came from a man who drowned in fresh water.

It’s the first time that transplanted organs have been identified as the likely source of a case of Legionnaires’ disease, the Centers for Disease Control and Prevention said in a report, adding that doctors and public health officials should be aware of the potential of a Legionnaires’ infection in organs taken from drowning victims.

Legionella, the class of bacteria that cause Legionnaires’ disease, live in bodies of fresh water. Legionnaires’ disease, a form of pneumonia, is typically spread by inhaling water droplets that contain the bacteria.

It was first identified in Philadelphia in 1976, when an outbreak among attendees of an American Legion convention at the Bellevue-Stratford Hotel in Center City left 182 people sickened and 29 dead. It was later discovered that Legionella had been living in the hotel’s air-conditioning system.

Cases of Legionnaires’ disease have been rising “substantially” in the last 10 years, the CDC said. While it’s difficult to trace the source of most cases, about 18% are associated with a health care facility.

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In the CDC’s report, researchers said that the lungs linked to the two recent cases were donated from a man in his 30s who fell into a river and was underwater for more than five minutes. Seven days later, his organs were removed for donation. No one suspected that the man had been exposed to Legionella, and the organs were not tested for the bacteria.

In May 2022, a woman in her 70s received a right-lung transplant at Temple. The CDC did not name the hospital in its report, but a Temple spokesperson later confirmed that the transplant had taken place there.

Nine days later, the woman had developed anemia and a high white blood cell count. In early June 2022, a biopsy of her transplanted lung tested positive for Legionella bacteria. She was treated with antibiotics and made a full recovery.

After the woman’s case was identified, doctors tested the recipient of the donor’s left lung, a man in his 60s who received the transplant at the same day at the same hospital. He tested positive for a different strain of Legionella. The man recovered from his infection, but he had suffered several complications after his transplant surgery, and died six months later from respiratory failure, the CDC reported.

The city and state health departments looked at testing records for water systems and cooling towers at Temple. Though the hospital did not regularly test for Legionella in its water supply, the CDC said, the records showed the hospital had a “well-functioning water management system,” and health officials could find no other cases of Legionnaires’ disease at the hospital within the previous six months. In the following six months, no one else at the hospital was infected, either.

In a statement, a Temple spokesperson said that the hospital “strictly follows all protocols to protect immunocompromised transplant patients.” The hospital had a one-year survival rate of 92% for lung transplant patients in 2022, the best in the region, and above national averages, the hospital said.

The lack of other Legionnaires cases at Temple led authorities to conclude that the source of the infection was likely the transplanted lungs. A few cases of Legionnaires’ disease have been traced to incidents where people who nearly drowned had aspirated Legionella bacteria. Transplant patients are also at a higher risk for contracting Legionnaires because of drugs they take to suppress their immune systems and encourage their bodies to accept the transplant.

But, until now, the CDC had not found a case of Legionella spreading through a lung transplant.

Researchers said that they were able to point to the transplanted lungs as the infection source because the patients were infected with different Legionella strains — which could indicate that the infection came from river water, which can harbor a number of different types of bacteria.

The hospital’s well-maintained water system and lack of any other cases also pointed to an infection source outside the facility.

The CDC acknowledged they couldn’t fully rule out other sources of infection. The hospital’s water supply wasn’t tested before or directly after the transplant operations. Neither were the lungs before their donation, and researchers couldn’t obtain specimens from the transplant patients for follow-up testing.

And, while no recipients of the donor’s other organs, including the heart and kidneys, developed Legionnaires’ disease, they were also not tested for the bacteria.

Still, the agency said, the finding presents new challenges for public health officials hoping to limit the spread of Legionella.

Transplant doctors should be more wary of the possibility of a Legionnaires’ infection in patients who received organs from donors who drowned in fresh water, and could consider prescribing medications to combat microbes that live in water, the agency said.

Temple representatives said they were glad that the CDC was informing transplant centers of the new risk.

“High quality, safe care for all of our patients is our top priority,” the hospital said in its statement. “This provides important guidance for all transplant teams, including here at Temple.”

Editor’s note: This story has been updated to include a comment from Temple University Hospital.