Analysis of nontuberculous mycobacteria infection risks from CDC’s water-related healthcare outbreak consultations, 2018–2024

Abstract Objective: Nontuberculous mycobacteria (NTM) are commonly found in healthcare facility water systems and can lead to serious and difficult-to-treat infections. We analyzed Centers for Disease Control and Prevention (CDC) consultations of water-related healthcare-associated infections (HAI) investigations involving NTM. Design: Retrospective observational study. Methods: We searched CDC consultation records from January 1, 2018, through December 31, 2024, using water-related terms and organisms, excluding Legionella , to identify and review investigations involving potential or confirmed transmission of water-related organisms; we reviewed investigations that involved NTM. Results: Among 1,458 consultations, we identified 639 (43.8%) water-related investigations involving 4,685 patients and 60 different organisms. Investigations involving NTM accounted for 10.3% (n = 66) with 15 NTM species identified. Among NTM-related investigations, almost half involved M. abscessus (n = 31, 47.0%) and two-thirds (n = 44, 66.7%) involved extrapulmonary infections only. More than half of identified NTM investigations (n = 37, 56.1%) occurred in hospitals and over one-third (n = 23, 34.8%) in outpatient settings. Exposures to surgery (n = 27, 40.9%) and medical products (e.g., medical devices, medications, and biological products) (n = 35, 53.0%) were common. Conclusions: Over this seven-year period, approximately one-tenth of CDC healthcare water-related consultations involved NTM. The majority involved extrapulmonary infections, with surgery and exposure to contaminated medical products representing the most common exposures of concern. These findings highlight the potential for NTM infections when water-related healthcare exposures occur. Healthcare facilities are encouraged to identify the potential for exposure to nonsterile water during surgery, during the use of medical devices, and during the preparation and administration of medications to reduce the risk from NTM.