Two consecutive outbreaks caused by chlorhexidine mouthwash contaminated with Burkholderia contaminans in a two-hospital tertiary care system.

ABSTRACT

BACKGROUND: Hospital outbreaks caused by Burkholderia spp. have been linked to contamination of several medical solutions and products and are frequently associated with delayed detection and high mortality. AIM: To describe the management of two consecutive Burkholderia contaminans outbreaks caused by contaminated mouthwash of different brands during the COVID-19 pandemic. METHODS: This was a retrospective cohort study of all patients involved in two outbreaks caused by B. contaminans detected in 2021 and 2022. The investigation was initiated after a cluster of positive respiratory specimens, followed by retrospective and prospective case-finding. FINDINGS: A total of 69 patients were affected, 47 in 2021 and 22 in 2022. The majority of affected patients had positive respiratory specimens (85.5%); 55.1% of cases had COVID-19, and 72.5% had multidrug-resistant organisms. Almost all (97.1%) patients required ventilation and 42.0% died. Seventeen percent of cases in the first outbreak were deemed to have been acquired by patient-to-patient transmission, whereas all of the cases in the second outbreak were infected directly from using mouthwash. The experience gained from the first outbreak and the formation of a multidisciplinary Infection Control Rapid Response Team resulted in more rapid recognition and control of the second outbreak. Multivariate analysis showed that older age, intensive care unit admission, and COVID-19 infection were independent predictors of mortality. CONCLUSION: Burkholderia outbreaks at the time of COVID-19 were associated with high mortality. Rapid detection and response by a dedicated experienced team (as in the second outbreak) can reduce mortality and prevent superimposed cross-transmission between patients.