Increased 30-day All-cause Mortality Associated with Gram-negative Bloodstream Infections in England During the COVID-19 Pandemic

Background: Our aim was to assess the impact of COVID-19 pandemic on mortality in patients hospitalised with Gram-negative bloodstream infections (GNBSIs).

Methods: A retrospective cohort study including cases of Escherichia coli, Klebsiella species and Pseudomonas aeruginosa in England (January 2015-December 2021) reported to UKHSA's Second Generation Surveillance System. The outcome was 30-day all-cause mortality. Multivariable logistic regression models were built, and adjusted Odds Ratios (ORs) with 95% confidence intervals were reported.

Results: Total E. coli, Klebsiella spp. and P. aeruginosa infections were 206,030, 53,819 and 21,129, respectively. Compared to the pre-pandemic period, odds of death during the pandemic (March 2020 onwards) in E. coli, Klebsiella spp. and P. aeruginosa infections with no COVID-19 infection within 28-days of onset were 1.13 (1.08-1.18), 1.15 (1.07-1.25) and 1.09 (0.97-1.22), while odds in GNBSIs with an associated COVID-19 infection were 2.45 (2.26-2.66), 2.96 (2.62-3.34) and 3.15 (2.61-3.80), respectively. Asian patients with an associated COVID-19 infection were more likely to die during the pandemic compared to White patients (E. coli: OR 1.28 (0.95-1.71); Klebsiella spp. OR 1.59 (1.20-2.11); P. aeruginosa: OR 2.02 (1.23-3.31)).

Conclusions: Patients suffering from a GNBSI had increased risk of death during the pandemic, with the risk higher in patients with an associated COVID-19 infection.