Proximity of UPMC Presbyterian's Legionella to VA just a coincidence
Just a 10-minute walk separates UPMC Presbyterian from the Veterans Affairs Pittsburgh Healthcare System in Oakland, the hubs of two clusters of Legionnaires' disease during the past three years.
But confirmation this week of Legionnaires' cases at Presby should not raise red flags over the neighborhood water supply, a leading microbiologist said. Tainted ice machines blamed in the Presby cases are a rare source for the disease, caused when immune-compromised people inhale common Legionella bacteria from contaminated water or mist, said Janet E. Stout, director at the Uptown-based Special Pathogens Laboratory.
The Tribune-Review reported Thursday on the Presby incident, in which one patient died and two fell ill last year after chewing on the hospital's ice chips. UPMC officials are sterilizing about 500 ice machines throughout its 20-hospital network, including 90 at Presby.
Six veterans died and 16 were sickened from February 2011 to November 2012 in the VA outbreak, which federal reviewers linked to bacteria-contaminated tap water and poor management of internal water systems.
“The concept of eliminating Legionella from every nook and cranny — it's not really something that can be achieved,” Stout said. She said ice machines are a much lower risk than hospitals' hot-water systems, where Legionella can multiply on a larger scale and reach more patients.
Stout wrote in 1985 about the presence of Legionella in hospital ice machines. Since then, federal guidelines and hospital policies for Legionella control have focused on safeguarding hot-water systems from Legionella through specialized ionization systems and chemical treatments.
The federal Centers for Disease Control and Prevention would not respond on Friday to Trib questions about its ice machine cleanliness guidelines, though Stout said the agency published discussion about the machines as possible harbors for bacteria. The CDC recommends periodic maintenance and cleaning, she said. Hospital workers at Presby identified the first patient with hospital-acquired Legionnaires' in October. Two patients developed the disease in December, UPMC officials said.
Workers traced the Legionella to ice machines when the general water supply tested negative for the bacteria. Machines returning to service are being sterilized and fitted with specialized filters to block Legionella, which Stout and UPMC officials said can multiply in warm reservoirs inside the machines. Stout has worked as an associate professor at UPMC's academic partner, the University of Pittsburgh.
UPMC notified the Allegheny County Health Department within 24 hours of discovering the cases, as state guidelines require, said health department Director Dr. Karen Hacker. She said her department's investigation began in November.
Hacker found UPMC “went beyond what is typical” in its response. She echoed Stout in saying the hospital's proximity to the VA outbreak is no cause for concern. The Pittsburgh Water and Sewer Authority, which serves both complexes, does not test for Legionella but chlorinates and filters its water, said spokeswoman Melissa Rubin.
“We are required by federal law to ensure our disinfectant level is adequate to remove or drastically reduce the health effects of microbial” organisms, Rubin said.
Legionella occurs naturally in the environment, and Western Pennsylvania's combination of abundant water and old plumbing mean the region has more of the bacteria than most places, Hacker said.
She said the health department receives 70 to 100 reports of Legionnaires' disease each year.
“Most are not acquired in a hospital. Most are community-acquired, which makes it very hard to identify the source,” Hacker said.
Western Pennsylvania's elevated reports of Legionnaires' stems in part from strong awareness of the Legionella risk, Stout said. County health guidelines since 1993 have urged hospitals to test proactively for Legionella.
Local rates of hospital-acquired Legionnaires' have slipped since then, Stout said. State reports show 417 of at least 1,910 Legionnaires' cases statewide between 2008 and 2013 involved Allegheny County residents. Nearly 8 percent of the local cases were fatal.
Stout said ice machines probably will gain more attention as microbiologists continue to raise awareness of the Legionella threat. She suggested Legionella-stopping filters for machines that serve the most vulnerable patients, such as transplant recipients, but doesn't think the method needs to be widespread.
“It's an underrecognized source of risk in hospitals,” said Dr. Joseph S. Cervia, a Legionnaires' expert and clinical professor of medicine at Hofstra North Shore-LIJ School of Medicine in Hempstead, N.Y. He said many Legionnaires' cases likely go undiagnosed.
“Many facilities don't do all they potentially could to reduce the risk,” Cervia said.
Adam Smeltz and Mike Wereschagin are Trib Total Media staff writers.