Boston—Is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) “just another flu,” as some critics of the public health response have claimed?
Jeremy Samuel Faust, MD, MS, of Harvard Medical School, Brigham and Women’s Hospital, and Carlos del Rio, MD, of Emory University School of Medicine and the Rollins School of Public Health, explain why that is not the case.
Their Viewpoint article in JAMA Internal Medicine points out that part of the misunderstanding might have been that, as of early May 2020, about 65,000 people in the United States had died of COVID-19, which appear similar to the estimated number of seasonal influenza deaths reported annually by the CDC. (The number had risen to around 100,000 by the end of May.)
“This apparent equivalence of deaths from COVID-19 and seasonal influenza does not match frontline clinical conditions, especially in some hot zones of the pandemic where ventilators have been in short supply and many hospitals have been stretched beyond their limits,” the authors argue. “The demand on hospital resources during the COVID-19 crisis has not occurred before in the U.S., even during the worst of influenza seasons. Yet public officials continue to draw comparisons between seasonal influenza and SARS-CoV-2 mortality, often in an attempt to minimize the effects of the unfolding pandemic.”
Drs. Faust and del Rio suggest there might be a misunderstanding of how seasonal influenza and COVID-19 data are publicly reported. The CDC, like many similar disease control agencies around the world, presents seasonal influenza morbidity and mortality not as raw counts but as calculated estimates based on submitted International Classification of Diseases codes, they explain. The result is that estimated influenza deaths—between 2013-2014 and 2018-2019, the reported yearly estimated influenza deaths ranged from 23,000 to 61, 000—actually were six times greater than counted influenza deaths, which were between 3,448 and 15,620 annually in that time period.
COVID-19 fatalities, on the other hand, are at present being counted and reported directly, not estimated. Drs. Faust and del Rio maintain that a more valid comparison would be to compare weekly counts of COVID-19 deaths to weekly counts of seasonal influenza deaths.
During the week ending April 21, 2020, they note, 15,455 COVID-19 counted deaths were reported in the United States, with the reported number of counted deaths from the previous week, ending April 14, totaling 14,478. Counted deaths during the peak week of the influenza seasons from 2013-2014 to 2019-2020 ranged from 351 (2015-2016, week 11 of 2016) to 1,626 (2017-2018, week 3 of 2018, according to the CDC, which calculated that the mean number of counted deaths during the peak week of influenza seasons from 2013-2020 was 752.4 (95% CI, 558.8-946.1).
“These statistics on counted deaths suggest that the number of COVID-19 deaths for the week ending April 21 was 9.5-fold to 44.1-fold greater than the peak week of counted influenza deaths during the past seven influenza seasons in the U.S., with a 20.5-fold mean increase (95% CI, 16.3-27.7),” the authors write.
The Viewpoint also emphasizes that those ratios are “more clinically consistent with frontline conditions than ratios that compare COVID-19 fatality counts and estimated seasonal influenza deaths.”
The authors conclude that directly comparing data “for two different diseases when mortality statistics are obtained by different methods provides inaccurate information. Moreover, the repeated failure of government officials and others in society to consider these statistical distinctions threatens public health. Government officials may rely on such comparisons, thus misinterpreting the CDC’s data, when they seek to reopen the economy and de-escalate mitigation strategies. Although officials may say that SARS-CoV-2 is ‘just another flu,’ this is not true.”
Drs. Faust and del Rio end the piece urging that SARS-CoV-2 mortality and seasonal influenza mortality be analyzed using “apples-to-apples comparison, not an apples-to-oranges comparison. Doing so better demonstrates the true threat to public health from Covid-19.”
The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.
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Jeremy Samuel Faust, MD, MS, of Harvard Medical School, Brigham and Women’s Hospital, and Carlos del Rio, MD, of Emory University School of Medicine and the Rollins School of Public Health, explain why that is not the case.
Their Viewpoint article in JAMA Internal Medicine points out that part of the misunderstanding might have been that, as of early May 2020, about 65,000 people in the United States had died of COVID-19, which appear similar to the estimated number of seasonal influenza deaths reported annually by the CDC. (The number had risen to around 100,000 by the end of May.)
“This apparent equivalence of deaths from COVID-19 and seasonal influenza does not match frontline clinical conditions, especially in some hot zones of the pandemic where ventilators have been in short supply and many hospitals have been stretched beyond their limits,” the authors argue. “The demand on hospital resources during the COVID-19 crisis has not occurred before in the U.S., even during the worst of influenza seasons. Yet public officials continue to draw comparisons between seasonal influenza and SARS-CoV-2 mortality, often in an attempt to minimize the effects of the unfolding pandemic.”
Drs. Faust and del Rio suggest there might be a misunderstanding of how seasonal influenza and COVID-19 data are publicly reported. The CDC, like many similar disease control agencies around the world, presents seasonal influenza morbidity and mortality not as raw counts but as calculated estimates based on submitted International Classification of Diseases codes, they explain. The result is that estimated influenza deaths—between 2013-2014 and 2018-2019, the reported yearly estimated influenza deaths ranged from 23,000 to 61, 000—actually were six times greater than counted influenza deaths, which were between 3,448 and 15,620 annually in that time period.
COVID-19 fatalities, on the other hand, are at present being counted and reported directly, not estimated. Drs. Faust and del Rio maintain that a more valid comparison would be to compare weekly counts of COVID-19 deaths to weekly counts of seasonal influenza deaths.
During the week ending April 21, 2020, they note, 15,455 COVID-19 counted deaths were reported in the United States, with the reported number of counted deaths from the previous week, ending April 14, totaling 14,478. Counted deaths during the peak week of the influenza seasons from 2013-2014 to 2019-2020 ranged from 351 (2015-2016, week 11 of 2016) to 1,626 (2017-2018, week 3 of 2018, according to the CDC, which calculated that the mean number of counted deaths during the peak week of influenza seasons from 2013-2020 was 752.4 (95% CI, 558.8-946.1).
“These statistics on counted deaths suggest that the number of COVID-19 deaths for the week ending April 21 was 9.5-fold to 44.1-fold greater than the peak week of counted influenza deaths during the past seven influenza seasons in the U.S., with a 20.5-fold mean increase (95% CI, 16.3-27.7),” the authors write.
The Viewpoint also emphasizes that those ratios are “more clinically consistent with frontline conditions than ratios that compare COVID-19 fatality counts and estimated seasonal influenza deaths.”
The authors conclude that directly comparing data “for two different diseases when mortality statistics are obtained by different methods provides inaccurate information. Moreover, the repeated failure of government officials and others in society to consider these statistical distinctions threatens public health. Government officials may rely on such comparisons, thus misinterpreting the CDC’s data, when they seek to reopen the economy and de-escalate mitigation strategies. Although officials may say that SARS-CoV-2 is ‘just another flu,’ this is not true.”
Drs. Faust and del Rio end the piece urging that SARS-CoV-2 mortality and seasonal influenza mortality be analyzed using “apples-to-apples comparison, not an apples-to-oranges comparison. Doing so better demonstrates the true threat to public health from Covid-19.”
The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.
« Click here to return to Weekly News Update.
