Ann Intern Med

Study examines impact of pandemic on antimicrobial resistance in U.S. hospitals

May 1, 2025

Study details: This retrospective cohort study analyzed antimicrobial resistance (AMR) trends in 243 U.S. hospitals during the COVID-19 pandemic. It focused on adult hospitalizations, excluding inpatient transfers, across three periods: prepandemic, peak pandemic, and waning pandemic. The study measured the incidence of various antibiotic-resistant infections, including methicillin-resistant Staphylococcus aureus and carbapenem-resistant Enterobacterales, among 120 hospitals continuously reporting data.

Results: There was a significant increase in antibiotic-resistant infections during the peak pandemic period, rising from 182 to 193 per 10,000 hospitalizations (6.5% increase). Hospital-onset AMR infections increased by 31.5%, driven by factors such as illness severity (ICU admission, mechanical ventilation, vasopressors, COVID-19 diagnosis), comorbidities, and prior antibiotic exposure. As the pandemic waned, overall AMR prevalence returned to prepandemic levels, but hospital-onset AMR remained elevated.

Clinical impact: Findings highlight the sustained increase in hospital-onset AMR infections during the COVID-19 pandemic, emphasizing the need for improved antibiotic stewardship and infection control measures. The study underscores the importance of addressing antibiotic exposure as a key risk factor for resistance, which persisted even as the pandemic's impact diminished.

Source:

Yek C; National Institutes of Health Antimicrobial Resistance Outcomes Research Initiative; et al. (2025, April 29). Ann Intern Med. Impact of the COVID-19 Pandemic on Antibiotic Resistant Infection Burden in U.S. Hospitals : Retrospective Cohort Study of Trends and Risk Factors. https://pubmed.ncbi.nlm.nih.gov/40294418/