October 21, 2016 — The bacteria that causes Legionnaires’ disease was detected in heater-cooler units at a hospital in Seattle where four patients were infected, including two who died.
The bacteria Legionella was also found in an ice machine and two sinks in the cardiac units at the University of Washington Medical Center, according to the Seattle Times.
The hospital is now contacting high-risk patients who may have been exposed between August 24 and September 13, 2016. This is the first outbreak of Legionnaires’ disease linked to heater-cooler units.
A spokeswoman for UW Medicine issued this statement:
“Legionnaires’ disease has not been previously proven to be transmitted in this fashion. We thoroughly cleaned and sanitized [the heater-cooler units] and took them out of service.”
Heater-cooler machines use water to control a patient’s body temperature during surgery. Water in the heater-cooler never directly touches the patient, but it does escape through the exhaust vents.
Any bacteria in the water can “aerosolize” in the operating room and land on patient undergoing surgery. Patients might also breathe the bacteria and develop a severe lung infection.
Legionnaires’ disease is a serious type of pneumonia (lung infection) caused by breathing in mist or water vapor that contains the bacteria.
It is not clear how Legionella got inside the heater-cooler machine, but the FDA has warned hospitals against filling the machine with tap water or ice made with non-sterile water. It is also possible that the machines were contaminated at the manufacturer in Germany.
The FDA has recently issued several warnings about another type of infection from heater-cooler units — M. Chimaera, a type of Non-Tuberculosis Mycobacterium (NTM) that can take years to cause symptoms. At least six hospitals in Ohio, Pennsylvania, and Michigan have had outbreaks, with 28 patients infected.