- Covid-19 was found to be more than three times more deadly than the flu among hospitalised patients
- The latest research was conducted in Canada, but similar studies also took place in the US and France
- Elderly patients are most likely to die, but younger patients are not exempt from risk
A study reveals that patients infected with Covid-19 could be at 3.5 times greater risk of death than patients battling a flu infection.
Research was conducted in Toronto and Mississauga, Canada, across seven hospitals in areas with large populations and high numbers of Covid-19 infections.
From 1 November 2019 to 30 June 2020, data from 1 027 patients admitted for Covid-19 and 783 admitted for flu were recorded (including individuals admitted to the ICU).
The study was published in the Canadian Medical Association Journal (CMAJ).
Of the 1 027 patients admitted for Covid-19, the median age was 65 years, and 59.1% were male.
Of the 783 patients admitted with flu, the median age was 68 years, and 50.8% were male.
Comparing the two groups, 19.9% of the patients with Covid-19 died in hospital, whereas only 6.1% of the patients with the flu died in hospital.
In a news release, clinician and researcher, Dr Amol Verma, said, “We can now say definitively that Covid-19 is much more severe than seasonal influenza.
“Patients admitted to hospital in Ontario with Covid-19 had a 3.5 times greater risk of death, 1.5 times greater use of the ICU, and 1.5 times longer hospital stays than patients admitted with influenza.”
The findings of these results were similar to those of studies conducted in the US and France.
In the US, research conducted by Washington University School of Medicine in St. Louis and Veterans Affairs St. Louis Health Care System, revealed clear differences between the two viruses.
A university news report stated that patients with Covid-19 needed more care than those with flu, and patients with Covid-19 had nearly five times the risk of death than those suffering from the flu.
The data collected showed that among 12 676 patients hospitalised with flu, 674 or 5.3% had died, whereas, among the 3 641 patients hospitalised with Covid-19, 676 or 18.5% had died.
Their cohort study was published in The BMJ toward the end of 2020.
The other cohort study conducted in France also found Covid-19 to be three times more deadly than the flu.
The study was conducted by researchers at the CHU hospital in Dijon, Côte d’Or, along with the medical research institute, Inserm.
A news report states that researchers counted 15 104 Covid-19-related deaths from 89 530 hospitalisations, between March and April 2020.
Between 1 December 2018 and 28 February 2019, they recorded 2 640 deaths out of the 45 819 hospitalisations for flu.
The French study was published in The Lancet Respiratory Medicine, also, at the end of 2020.
In all three studies, it was noted that many people think Covid-19 mainly affects the elderly.
In the most recent study conducted in Canada, Dr Verma added, “It is true that Covid-19 affects older adults more severely. We found that among adults over 75 years, who were hospitalised with Covid-19, nearly 40% died in hospital.
“But it can also cause very serious illness in younger adults. Adults under 50 accounted for 20% of all Covid-19 hospitalisations in the first wave of the pandemic.
“Nearly one in three adults younger than 50 hospitalised with Covid-19 required intensive care, and nearly one in 10 required an unplanned readmission to hospital after discharge.”
For a while, many people thought of the Covid-19 infection as similar to, if not the same as, a flu infection.
Covid-19 vs the flu
The Johns Hopkins Bloomberg School of Public Health Q&A states that it is “not at all accurate” to claim that Covid-19 is “just the flu”.
Andrew Pekosz, a virologist, and professor in the Department of Molecular Microbiology and Immunology says that since December 2019, Covid-19 has killed more people in the US than flu has in the last five years.
He added that while flu is certainly a significant burden on the population, Covid-19 “has had a vastly larger effect”.
“Many more people are susceptible to Covid-19 because there is little pre-existing immunity to the virus that causes it - SARS-CoV-2.
“Through vaccinations and previous infections, a portion of the population has some immunity to flu, which helps limit the number of cases we see each year.
"There is a lot of similarity between how the two viruses are spread, but the number of susceptible people is really what allows SARS-CoV-2 to spread so easily,” said Pekosz.