An outbreak within an outbreak: The impact of Infection Prevention and Control strategies on hospital-acquired infections and the occurrence of multi-drug resistant organisms during the COVID-19 pandemic.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic placed an unprecedented strain on intensive care units (ICUs) in South Africa. Infection prevention and control (IPC) strategies were highlighted to minimise the risk to healthcare workers and for the protection of patients from contracting hospital-acquired infections (HAIs). During the third wave, our institution adopted a shift system to address severe burnout among ICU personnel. We noted an upstroke in the occurrence of HAIs, specifically carbapenem-resistant Enterobacterales (CRE) and multidrug-resistant (MDR) Acinetobacter baumannii.

OBJECTIVES: To report these outbreaks, compare the rate of CRE and A. baumannii infections with the first COVID-19 wave and to analyse its impact on patient outcomes.

METHOD: We retrospectively analysed data from a prospectively collected registry involving all adult patients with severe COVID-19 admitted to the dedicated COVID-19 ICU from May 2021 to September 2021. Information from the admission database, including the patients' demographics, comorbidities, laboratory results and length of ICU stay were extracted.

RESULTS: Ninety patients were admitted with severe COVID-19 during the third wave. There was an outbreak of both CRE (the majority Klebsiella pneumoniae) and A. baumannii. Furthermore, 18 patients cultured the same CRE organism, and 25 patients cultured the environmental organism A. baumannii. The HAI rate was significantly higher compared with the first wave published data: 59/90 (65.6%) v. 73/363 (20.1%, p<0.01). Patients with any HAI had a longer mean stay in ICU (10.1 days v. 6.7 days (p<0.01) and a higher mortality of 48/59 (81%) v. 19/31 (61%) (p=0.05).

CONCLUSION: We observed a very significant rise in HAIs in the COVID-19 ICU during the third wave compared with the first, with almost three times as many patients developing HAIs. Unsurprisingly, it was associated with a longer mean stay in ICU and a higher mortality. The outbreak of both CRE and A. baumannii, and the fact that many patients cultured the same CRE organism and A. baumannii, strongly suggests that a critical breakdown in IPC measures had occurred.