COVID-19 far more deadly than seasonal flu, large study confirms

Reuters Health - 18/12/2020 - COVID-19 is far more serious than seasonal influenza, the largest study to date to compare the two diseases confirms.

Using French national data, researchers compared data on 89,530 patients hospitalized with COVID-19 between March and April 2020, with 45,819 patients hospitalized with seasonal influenza between December 2018 and February 2019.

Overall, illness was more severe for patients with COVID-19 than their peers with seasonal influenza. "Almost twice as many patients were hospitalized for COVID-19 than for seasonal influenza, over a shorter time period (2 months for COVID-19 and 3 months for seasonal influenza)," according to the Lancet Respiratory Medicine report.

The COVID-19 death rate was three times higher than for seasonal influenza (16.9% vs 5.8%), which is "particularly striking when reminded that the 2018/2019 flu season had been the worst in the past five years in France in terms of number of deaths," co-lead author Dr. Catherine Quantin, from Dijon University Hospital, said in a news release.

More patients with COVID-19 required admission to the intensive care unit (16.3% vs 10.8%) and the average ICU stay was nearly twice as long (15 days vs 8 days).

COVID-19 patients were also twice as likely as influenza patients to need invasive mechanical ventilation during their hospital stay (9.7% vs 4.0%). More than one quarter (27.2%) of COVID-19 patients suffered acute respiratory failure compared with 17.4% of influenza patients.

Consistent with other research, the most common comorbid medical conditions among hospitalized COVID-19 patients were hypertension, overweight or obesity and diabetes.

"Taken together, our findings clearly indicate that COVID-19 is much more serious than seasonal influenza. At a time when no treatment has been shown to be effective at preventing severe disease in COVID-19 patients, this study highlights the importance of all measures of physical prevention and underlines the importance of effective vaccines," co-lead author Dr. Pascale Tubert-Bitter, from University Paris-Saclay, said in the news release.

The researchers also report that fewer children younger than 18 years were hospitalized with COVID-19 compared with seasonal influenza (1.4% vs 19.5%), but a larger proportion of children younger than age 5 years with COVID-19 required ICU care (2.3% vs 0.9%).

In patients 11 to 17 years, the death rate appeared to be 10-fold higher in those hospitalized with COVID-19 compared to their peers admitted with influenza. However the authors caution that the numbers are too small to draw any meaningful conclusions. Among 11- to 17-year olds, five out of 548 (1.1%) with COVID died as did one out of 804 (0.1%) with seasonal influenza.

Writing in a linked Comment, Dr. Eskild Petersen, from the University of Aarhus, Denmark, notes that the large sample size is "an important strength of the study and it is assumed that the indication for hospital admission in the two periods were the same and thus does not bias the results. The results clearly demonstrate that COVID-19 was more serious than seasonal influenza."

Dr. Eskild says the findings also send important messages for COVID-19 vaccination efforts.

"Clearly people with obesity, diabetes, and hypertension must be considered high-risk groups, but the results also show that children and adolescents must be offered immunization, given that young people can also become severely ill. Even if healthcare workers and people older than 65 years are prioritized for the first rounds of immunizations, children and adolescents should also be offered the vaccine when it becomes available," Dr Eskild writes.

The study was funded by the French National Research Agency.

SOURCE: https://bit.ly/3nJuVjC The Lancet Respiratory Medicine, online December 17, 2020.

By Reuters Staff



Posted on 18 December 202022 December 2020