Mycobacterium chimaera molecular investigation

European Centre for Disease Prevention and Control (ECDC) alerted in June 2015 about open-chest surgical infections due to Mycobacterium chimaera. Although these infections are rare and difficult to diagnose, they were shown to have occurred throughout the world due to contamination of heater-cooler units (HCU) manufactured at one place mainly. We report the investigation results in France and the specific genomic comparison of patient and environmental isolates from HCU surveillance. Two successive investigations included a retrospective search for M. chimaera infection cases in 2015, and a survey in 2017 coupling good practices questionnaire with HCU microbial analysis. Mycobacterial isolates were submitted to whole genome sequencing (WGS) and compared to the outbreak strain.