Mycobacterium chelonae outbreak investigation at a quaternary pediatric hospital following the opening of a LEED-certified critical care tower: where does water sustainability intersect with infection control?

OBJECTIVE

Investigate the increased incidence of Mycobacterium chelonae positive respiratory cultures in hospitalized patients.

DESIGN

Apply the Healthcare-Associated Links in Transmission of Nontuberculous Mycobacteria (HALT NTM) toolkit to an outbreak investigation of M. chelonae.

SETTING

Quaternary-care pediatric hospital and medical center in the United States with a recently opened LEED-certified critical care tower.

PATIENTS: Adult and pediatric patients with M. chelonae positive respiratory cultures between June 2022 and January 2024.

METHODS

An epidemiological investigation involving clinical and laboratory practices, water management, building construction and renovation projects. Environmental sampling of air vents, water sources and endoscope reprocessing equipment was performed. M. chelonae isolates recovered from patients and the environment were analyzed using whole genome sequencing and compared for relatedness.

RESULTS

Three clusters of matching environmental and patient isolates were identified. The most common environmental source of M. chelonae was ice/water dispensers with 40% positivity of sampled units. The critical care tower's water system performance and metrics were suboptimal, leading to four physical remediation activities along with a hyperchlorination treatment.

CONCLUSIONS

Recent and ongoing construction along with the implementation of a LEED-certified, low-flow water system in a new critical care tower provided enhanced opportunities for M. chelonae exposure at point of use locations such as ice/water dispensers. More national infection prevention and control guidance is needed to address the infection risks from water sustainability efforts and construction activities in healthcare facilities.