Comparison between patients hospitalized for influenza and COVID-19 in a tertiary care center

This article was originally published here

J Gen Intern Med. March 18, 2021 doi: 10.1007 / s11606-021-06647-2. Online before printing.


BACKGROUND: Numerous reports suggest that the characteristics and course of coronavirus disease 2019 (COVID-19) and influenza disease differ, but detailed comparisons of their clinical manifestations are lacking.

OBJECTIVE: Comparison of the epidemiology and clinical characteristics of COVID-19 patients during the pandemic with those of influenza patients from previous influenza seasons in the same hospital DESIGN: Admission rate, clinical measures and clinical outcomes of confirmed cases of COVID- 19 between March 1 and April 30, 2020, were compared to those of confirmed influenza cases in the previous five influenza seasons (8 months each) starting September 1, 2014.

SETTING: Large Tertiary Care Teaching Hospital in Boston, MA PARTICIPANTS: Laboratory-confirmed COVID-19 and inpatients with influenza and critical care admissions.

RESULTS: Data was extracted from the medical records of 1052 influenza patients and 582 COVID-19 patients. On average, 210 influenza hospital admissions occurred per 8-month season, compared to 582 COVID-19 admissions over 2 months. The median weekly number of COVID-19 patients requiring mechanical ventilation was 17 (IQR: 4.34) compared to a weekly median of 1 (IQR: 0.2) influenza patient (p = 0.001). COVID-19 patients were significantly more likely to require mechanical ventilation (31% vs 8%) and had significantly higher mortality (20% vs 3%; p <0.001 for all). Relatively more mechanically ventilated COVID-19 patients had no pre-existing conditions compared to mechanically ventilated influenza patients (25% vs 4%, p <0.001). Pneumonia / ARDS secondary to the virus was the leading cause of mechanical ventilation in COVID-19 patients (94%) as opposed to influenza (56%).

LIMITATION: This is a single-center study which may limit generalization.

CONCLUSION: COVID-19 resulted in more weekly hospitalizations, higher morbidity and higher mortality than influenza in the same hospital.

PMID: 33738759 | DOI: 10.1007 / s11606-021-06647-2