Abstaining from the consumption of tap water at health care facilities can dramatically reduce the risk of Mycobacterium abscessus infections among patients and staff, according to a new study published in Clinical Infectious Diseases.
“Outbreaks of [M. abscessus] and other rapidly growing mycobacteria are common and have been associated with colonized plumbing systems in commercial buildings and health care facilities,” wrote the authors, led by Arthur W. Baker, MD, MPH, of Duke University, Durham, N.C., adding that “Infections due to M. abscessus are difficult to diagnose and typically require months of therapy using multiple antibiotics” (Clin Infect Dis. 2017 Jan 10. doi: 10.1093/cid/ciw877).
Dr. Baker and his colleagues tracked an outbreak of M. abscessus at a single institution – the Duke University Hospital. The outbreak was split into Phase 1 and Phase 2, along with a baseline period preceding both during January through July 2013. During baseline, the incidence rate of M. abscessus infections was 0.7 per 10,000 patient-days. However, during Phase 1 – which lasted from August 2013 through May 2014 – the rate jumped to 3.0 per 10,000 patient-days, yielding a rate ratio of 4.6 (95% confidence interval, 2.3-8.8; P less than .001).Phase 2 took place from December 2014 through June 2015; in between Phase 1 and Phase 2, tap water abstention was implemented to protect patients deemed high risk, such as those with lung transplants. Of the 71 infections that occurred during Phase 1, 39 (55%) were lung transplant patients, while 9 (13%) were in those who had a recent cardiac surgery, 5 (7%) had cancer, and 5 (7%) had hematopoietic stem cell transplants. Incidence rates decreased substantially, back to their baseline levels, and further measures were used to completely resolve the outbreak.
“Primary interventions included institution of an inpatient sterile water protocol for high-risk patients, implementation of a protocol for enhanced disinfection and sterile water use for [heater-cooler units] of [cardiopulmonary bypass] machines, and water engineering changes designed to decrease NTM [nontuberculous mycobacteria] burden in the plumbing system,” the authors explained. “Other health care facilities, particularly those with endemic NTM or newly constructed patient care facilities, should consider similar multifaceted strategies to improve water safety and decrease risk of health care–associated infection from NTM.”
The study was funded by the National Institutes of Health’s Transplant Infectious Disease Interdisciplinary Research Training Grant. Dr. Baker and his coauthors did not report any relevant financial disclosures.