An Outbreak of New Delhi Metallo-beta-lactamase Among Intensive Care Unit Patients in an Acute Care Hospital

BACKGROUND: The South Carolina Department of Health and Environmental Control (SCDHEC) was notified of a Klebsiella pneumoniae NDM isolated from a respiratory specimen of a patient in a dedicated Coronavirus Disease 2019 (COVID-19) intensive care unit (ICU) at an acute care hospital (ACH). NDM is a Tier 2 multi-drug resistant organism (MDRO), specifically a carbapenem-resistant Enterobacterales (CRE) which can cause serious infection and requires intervention to prevent spread. METHODS: The Healthcare-Associated Infections staff from SCDHEC collaborated with the hospital's infection preventionists (IP) to mitigate and prevent further transmission. CRE colonization screening and respiratory culture collection on the remaining eleven ICU patients was initiated. An onsite visit to the facility was conducted. This included a discussion of steps the facility had taken since initial notification of the NDM-positive patient and observation of infection control practices in the dedicated COVID-19 ICU. A modified assessment tool based on the Centers for Disease Control and Prevention's infection control assessment and response (ICAR) tool was used. RESULTS: CRE colonization screenings were all negative; however, respiratory cultures identified two additional patients positive with NDM. Upon investigation, an infection control breach was discovered, stemming from nonconventional use of personal protective equipment (PPE) during the COVID-19 pandemic. It was found that staff working with the positive NDM-patients were not re-educated on proper contact precautions and use of PPE. After the infection control assessment, a list identifying the unit's strengths, weaknesses, opportunities, and threats was shared with the IPs as a guide for practice improvement and transmission disruption. CONCLUSIONS: The NDM outbreak was limited to the initial patient and the additional two discovered during active culture surveillance. The infection control assessment found that nonconventional infection prevention and control practices deployed during the COVID-19 pandemic led to unintentional spread of MDROs; however, early interventions in collaboration with public health can prevent further transmission.