To evaluate whether rates of healthcare-associated infections (HAIs) changed during the coronavirus disease 2019 (COVID-19) pandemic in malignant hematology and stem cell transplant patients.

A retrospective, cohort study.

The study included malignant hematology and stem cell transplant patients admitted between March 1, 2019, through July 31, 2019, and March 1, 2020, through July 31, 2020.

Rates of catheter-associated urinary tract infections (CAUTIs), central-line–associated bloodstream infections (CLABSIs), central-line–associated mucosal barrier injury infections (CLAMBIs), and Clostridioides difficile infections (CDIs) during the pandemic were compared to those in a control cohort. Secondary outcomes included the rate of non–COVID-19 respiratory viruses.

The rate of CAUTIs per 1,000 hospital days was 0.435 before the pandemic and 0.532 during the pandemic (incidence rate ratio [IRR], 1.224; 95% confidence interval [CI], 0.0314–47.72; P = .899). The rate of CLABSIs was 0.435 before the pandemic and 1.064 during the pandemic (IRR, 2.447; 95% CI, 0.186–72.18; P = .516). The rate of CLAMBIs was 2.61 before the pandemic and 1.064 during the pandemic (IRR 0.408, 95% CI 0.057–1.927; P = .284). The rate of CDIs was 2.61 before the pandemic and 1.579 during the pandemic (IRR, 0.612; 95% CI, 0.125–2.457; P = .512). Non–COVID-19 respiratory virus cases decreased significantly from 12 (30.8%) to 2 cases (8.3%) (P = 0.014).

There was no significant difference in HAIs among inpatient malignant hematology and stem cell transplant patients during the COVID-19 pandemic compared to those of a control cohort. Rates of infection were low among both cohorts. Rates of community-acquired respiratory viruses decreased significantly during the pandemic among this population.