303. Viral and bacterial infections among adults hospitalized with COVID-19, Coronavirus Disease 2019-Associated Hospitalization Surveillance Network, 14 states, March 2020–February 2022

BACKGROUND: Coinfections, both bacterial and viral, occur with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but prevalence, risk factors, and associated clinical outcomes are not fully understood. METHODS: We used the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET), a population-based surveillance platform to investigate the occurrence of viral and bacterial coinfections among hospitalized adults with laboratory-confirmed SARS-CoV-2 infection during March 2020 and February 2022. Patients receiving additional standard of care (SOC) molecular testing for viral pathogens (14 days prior to admission or 7 days after), including respiratory syncytial virus, rhinovirus/enterovirus (RV/EV), influenza, adenovirus, human metapneumovirus, parainfluenza viruses, and endemic coronaviruses, were included. SOC testing for clinically relevant bacterial pathogens (7 days before admission or 7 days after) from sputum, deep respiratory, and sterile sites were included. The demographic and clinical features of those with and without bacterial infections were compared. RESULTS: Among 2,654 adults hospitalized with COVID-19 and tested for all 7 virus groups, another virus was identified in 3.1% of patients. RV/EV (1.2%) and influenza (0.4%) were the most commonly detected viruses. Half (17,842/35,528, 50.2%) of hospitalized adults with COVID-19 had bacterial cultures taken within 7 days of admission, and 1,092 (6.1%) of these had a clinically relevant bacterial pathogen. A higher percentage of those with a positive culture died compared to those with negative cultures (32.3% vs 13.3%, p< 0.001). Staphylococcus aureus was the most common isolate overall; Pseudomonas aeruginosa was the second most common respiratory isolate (Figure 1). [Figure: see text] This figure includes 1,408 bacterial cultures from 1,066 individuals. Deep respiratory sites include endotracheal aspirate, bronchoalveolar lavage fluid, bronchial washings, pleural fluid, and lung tissue. Commensal organisms were excluded. CONCLUSION: Consistent with previous studies, a relatively low proportion of adults hospitalized with COVID-19 had concomitantly identified viral or bacterial infections. Identification of a bacterial infection within 7 days of admission is associated with increased mortality among adults hospitalized with COVID-19. Conclusions about the clinical relevance of bacterial infections is limited by the retrospective nature of this study. DISCLOSURES: Evan J. Anderson, MD, GSK: Advisor/Consultant|GSK: Grant/Research Support|Janssen: Advisor/Consultant|Janssen: Grant/Research Support|Kentucky Bioprocessing, Inc: Data Safety Monitoring Board|MedImmune: Grant/Research Support|Medscape: Advisor/Consultant|Merck: Grant/Research Support|Micron: Grant/Research Support|NIH: Funding from NIH to conduct clinical trials of Moderna and Janssen COVID-19 vaccines|PaxVax: Grant/Research Support|Pfizer: Advisor/Consultant|Pfizer: Grant/Research Support|Regeneron: Grant/Research Support|Sanofi Pasteur: Advisor/Consultant|Sanofi Pasteur: Grant/Research Support|Sanofi Pasteur: Data Adjudication and Data Safety Monitoring Boards|WCG and ACI Clinical: Data Adjudication Board.