Send to:

Choose Destination
See comment in PubMed Commons below
Clin Infect Dis. 2015 Jul 1;61(1):67-75. doi: 10.1093/cid/civ198. Epub 2015 Mar 11.

Prolonged Outbreak of Mycobacterium chimaera Infection After Open-Chest Heart Surgery.

Author information

  • 1Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich.
  • 2Institute of Medical Microbiology, National Centre for Mycobacteria, University of Zurich.
  • 3Institute of Surgical Pathology.
  • 4Division of Cardiac Surgery, University Hospital Zurich, Switzerland.



Invasive Mycobacterium chimaera infections were diagnosed in 2012 in 2 heart surgery patients on extracorporeal circulation. We launched an outbreak investigation to identify the source and extent of the potential outbreak and to implement preventive measures.


We collected water samples from operating theaters, intensive care units, and wards, including air samples from operating theaters. Mycobacterium chimaera strains were characterized by randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). Case detection was performed based on archived histopathology samples and M. chimaera isolates since 2006, and the patient population at risk was prospectively surveyed.


We identified 6 male patients aged between 49 and 64 years with prosthetic valve endocarditis or vascular graft infection due to M. chimaera, which became clinically manifest with a latency of between 1.5 and 3.6 years after surgery. Mycobacterium chimaera was isolated from cardiac tissue specimens, blood cultures, or other biopsy specimens. We were able also to culture M. chimaera from water circuits of heater-cooler units connected to the cardiopulmonary bypass, and air samples collected when the units were in use. RAPD-PCR demonstrated identical patterns among M. chimaera strains from heater-cooler unit water circuits and air samples, and strains in 2 patient clusters.


The epidemiological and microbiological features of this prolonged outbreak provided evidence for the airborne transmission of M. chimaera from contaminated heater-cooler unit water tanks to patients during open-heart surgery.

© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail:


Mycobacterium chimaera; infection control; nontuberculous mycobacteria; open-chest heart surgery; outbreak

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk