Outbreak of Mycobacterium mucogenicum bacteraemia due to contaminated water supply in a paediatric haematology-oncology department.

We describe an outbreak of bloodstream infections due to Mycobacterium mucogenicum involving five patients in a paediatric haematology-oncology ward over a six-month period. Specimens from faucets on the floor indicated that an automatic faucet was the probable source of infection and identity between strains was confirmed using molecular techniques. Levels of chlorine in the water were intermittently low and may have contributed towards bacterial growth. A review of infection control practices revealed that the exit sites of central venous catheters (CVCs) of children were not properly covered during bathing, which may have facilitated CVC colonisation. Replacing the contaminated faucets, optimal water chlorination and proper coverage of the CVC exit site using impermeable dressings terminated the outbreak. This investigation emphasises the three major factors that should be investigated in outbreaks due to a waterborne pathogen: source of the infection, water supply and infection control practices.