Charges of in-hospital demise and intensive care unit (ICU) admissions had been related amongst adults hospitalized in Switzerland with healthcare-linked COVID-19 or influenza infections throughout SARS-CoV-2 Omicron variant predominance, researchers report in Medical Infectious Ailments.
Led by researchers from the An infection Management Program and the World Well being Group (WHO) Collaborating Heart at Geneva College Hospitals, the retrospective examine concerned 2,901 symptomatic COVID-19 sufferers and 868 flu sufferers at 9 hospitals. Instances recognized no less than 3 days after admission had been reported to the nationwide hospital surveillance program from February 2022 to April 2023 (COVID-19) or November 2018 to April 2023 (flu).
“These two illnesses characterize a considerable burden of respiratory sicknesses amongst hospitalized sufferers, notably in the course of the winter months in temperate climates,” the examine authors famous. “Hospitalized sufferers are sometimes at elevated threat for extreme COVID-19 or influenza, notably older adults, folks with weakened immune programs, and people with power circumstances.”
Extra problems with flu
Absolutely the variety of COVID-19 deaths was 3 times larger than these from flu, however the case-fatality ratio was comparable for COVID-19 (6.2%) and flu (6.1%); after adjustment, sufferers had a comparable subdistribution hazard ratio (HR) for 30-day in-hospital demise (0.91). Related percentages had been admitted to the ICU (2.4% COVID-19 vs 2.6% flu).
A better share of sufferers had been admitted to an intermediate care unit for COVID-19 (2.9%) than for flu (1.4%), and a better proportion of flu sufferers had problems than these with COVID-19 (35.3% vs 29.3%).
The adjusted cause-specific HR for in-hospital demise from flu versus COVID-19 was 0.94, and the cause-specific HR for flu-patient hospital launch in contrast with COVID-19 hospital launch was 1.04. The weighted subdistribution HR for flu demise, in contrast with these from COVID-19, with hospital discharge as a competing threat was 0.91.
Vaccination reveals protecting impact
Whereas there was no distinction in threat of demise by vaccination standing (no less than one dose vs none), hospital stays had been a median of two days longer (16 vs 14 days) amongst unvaccinated COVID-19 sufferers (16 vs 14 days) and flu sufferers (16 vs 11). Likewise, COVID-19 sufferers who had acquired the final of no less than 3 doses throughout the previous 12 months had shorter hospital stays than those that had been unvaccinated or had acquired a vaccine dose greater than a 12 months earlier than.
The impression of cumulative vaccine- and infection-derived immune responses possible explains the discount in hazard for in-hospital mortality for COVID-19 as in comparison with influenza.
“Whereas the relative hazard could also be comparable, you will need to acknowledge that absolutely the variety of sufferers with healthcare-associated COVID-19 (Omicron) was three-fold larger than the variety of sufferers with healthcare-associated influenza,” the researchers wrote. “COVID-19 subsequently nonetheless represents a considerably bigger medical burden for hospitals than influenza in Switzerland.”
The discovering of shorter hospital stays among the many vaccinated affirm vaccines’ protecting results, they mentioned.
“The impression of cumulative vaccine- and infection-derived immune responses possible explains the discount in hazard for in-hospital mortality for COVID-19 as in comparison with influenza, in addition to adjustments within the inherent virulence of pre-Omicron versus Omicron SARS-CoV-2 variants,” the authors wrote. “Though we additionally can not exclude that adjustments within the virulence of influenza strains and pre-existing immunity can also contribute to our observations.”
