Secondary bacterial infection in COVID-19 patients is a stronger predictor for death compared to influenza patients

Noa Shafran, Inbal Shafran, Haim Ben-Zvi, Summer Sofer, Liron Sheena, Ilan Krause, Amir Shlomai, Elad Goldberg, Ella H. Sklan*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

130 Scopus citations


Secondary bacterial infections are a potentially fatal complication of influenza infection. We aimed to define the impact of secondary bacterial infections on the clinical course and mortality in coronavirus disease 2019 (COVID-19) patients by comparison with influenza patients. COVID-19 (n = 642) and influenza (n = 742) patients, admitted to a large tertiary center in Israel and for whom blood or sputum culture had been taken were selected for this study. Bacterial culture results, clinical parameters, and death rates were compared. COVID-19 patients had higher rates of bacterial infections than influenza patients (12.6% vs. 8.7%). Notably, the time from admission to bacterial growth was longer in COVID-19 compared to influenza patients (4 (1–8) vs. 1 (1–3) days). Late infections (> 48 h after admission) with gram-positive bacteria were more common in COVID-19 patients (28% vs. 9.5%). Secondary infection was associated with a higher risk of death in both patient groups 2.7-fold (1.22–5.83) for COVID-19, and 3.09-fold (1.11–7.38) for Influenza). The association with death remained significant upon adjustment to age and clinical parameters in COVID-19 but not in influenza infection. Secondary bacterial infection is a notable complication associated with worse outcomes in COVID-19 than influenza patients. Careful surveillance and prompt antibiotic treatment may benefit selected patients.

Original languageEnglish
Article number12703
JournalScientific Reports
Issue number1
StatePublished - Dec 2021


FundersFunder number
Milner Foundation


    Dive into the research topics of 'Secondary bacterial infection in COVID-19 patients is a stronger predictor for death compared to influenza patients'. Together they form a unique fingerprint.

    Cite this