A fifth patient at a central Pennsylvania died after being infected with a nontuberculous mycobacteria, according to an article on the Philly.com website
In all cases, the hospitals used a "heater-cooler" device to control the patients' body temperatures while they were on a heart-bypass machine.
These machines contain circulating water that does not come into direct contact with the patient. But experts say that if bacteria are present in the water, it can infect patients when it becomes aerosolized through the device's exhaust vent.
The latest patient, who underwent surgery at WellSpan York Hospital, was among eight who became infected in the past several years
The Pennsylvania Department of Health required both hospitals to replace its heater-coolers.
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