MYCOBACTERIUM CHIMAERA INFECTIONS AFTER CARDIOVASCULAR SURGERY: LESSONS FROM A GLOBAL OUTBREAK.

A global outbreak of invasive Mycobacterium chimaera infections has been associated with exposure to certain heater-cooler devices (HCDs) used during cardiopulmonary bypass. Outbreak investigations have shown that these HCDs harbor M. chimaera in water circuits and generate bio-aerosols in the operating room, leading to airborne transmission to patients during surgery. Whole genome sequencing data support a common-source outbreak originating at an HCD manufacturing facility. Most clinical infections are associated with implanted devices, diagnosis is often delayed, and treatment requires device removal and prolonged antibiotic therapy. Because it is nearly impossible to eradicate M. chimaera from HCDs using existing disinfection approaches, strict separation of HCD exhaust from operating room air is necessary to prevent patient exposure. Lessons learned from this outbreak include: 1) medical device risks are difficult to predict, requiring improved expert review before approval, and 2) advances in genomics provide powerful tools for outbreak investigation and public health surveillance.