Impact of the COVID-19 pandemic on the incidence and the epidemiology of catheter-related bloodstream infection two years later.

Introduction: The COVID-19 pandemic increased catheter-related bloodstream infections (C-RBSI), but its subsequent impact has not been adequately described. Our hospital has already depicted the effects of the COVID-19 pandemic in the first wave. However, we still do not know whether C-RBSI rates and aetiology are similar to those described before the COVID-19 pandemic. We aimed to evaluate the impact of the COVID-19 pandemic on the evolution of C-RBSI in a large tertiary teaching hospital two years later. Material and methods: We prospectively collected all confirmed C-RBSI episodes in a clinical microbiology laboratory database by matching blood cultures and catheter tip cultures with the isolation of the same microorganism (s). We compared our C-RBSI incidence rates and aetiology from 2018 to 2023. C-RBSI was defined as bacteremia or fungemia in a patient with clinical manifestations of infection and no other apparent source except the catheter. Results: During the study period, we collected 556 C-RBSI episodes. C-RBSI incidence rate per 1000 admissions each year was as follows: 2018: 2.2; 2019: 1.7; 2020: 3.29; 2021: 2.92; 2022: 2.69. and 2023: 2.01. Mainly, C-RBSI episodes occurring in critical care units each year were, respectively: 2018: 57 (54.8 %), 2019: 38 (45.2 %), 2020: 89 (63.6 %), 2021: 69 (60.5 %), 2022: 58 (50.9 %) and 2023 (61.4 %). The distribution of microorganisms showed an increase in Gram-negative episodes after the pandemic. Conclusion: Our study shows an increase in the incidence rate of C-RBSI during the COVID-19 pandemic, with a discrete decrease after that. C-RBSI episodes were mainly caused by coagulase-negative Staphylococci but with a rise in Gram-negative bacilli.