Outbreak of Candida parapsilosis fungemia in an intensive care unit during a COVID surge: an epidemic within a pandemic

We sought to investigate epidemiology, risk factors, clinical features, and outcome of the C. parapsilosis blood stream infection (BSI) outbreaks observed during the first surges of COVID-19 pandemic in our population. Retrospective, monocentric observational study in the 24 bed intensive care unit (ICU) of a tertiary care medical center in northern Italy, from 2019 to 2021 first 5 months. 2030 patients were enrolled, of whom 239 were COVID-19 positive. The total incidence of Candida-BSI was 41.9 per 1000 admissions, with two outbreaks during 2020 spring and winter's COVID surges. The total numbers of C. parapsilosis BSI cases are 94, of which 21 during the first outbreak and 20 during the second. In our population, COVID-19 was strongly associated with C. parapsilosis BSI (OR 4.71, p < 0.001), as well as continuous renal replacement therapy (CRRT) (OR 3.44, p = 0.001), prolonged antibiotic therapy (OR 3.19, p = 0.004), and delayed infusion sets replacements (OR 2.76, p = 0.015). No statistically significant association was found between Candida-BSI episodes and mortality, when adjusted for other known outcome risk factors. COVID surges undermined the infectious control measures in our ICU, leading to two outbreak of C. parapsilosis BSI. A stricter, thorough management of intravascular devices and infusion set is crucial in prevention of catheter related BSI, and awareness must be kept high, especially in emergencies circumstances, such as the ongoing COVID-19 pandemic.