CDC Reduces COVID-19 Fatality Rate to 0.26 Percent
Published June 1, 2020 | Health, Infections
In a new document providing guidance for public health officials on COVID-19, the U.S. Centers for Disease Control and Prevention (CDC) estimates the infection fatality rate (IFR) for the disease at 0.4 percent, or about half the nearly one percent fatality rate the CDC estimated in March 2020 when it was predicting up to 1.7 million COVID-19 deaths in the United States.1 2 3 4 5 6
According to the document COVID-19 Pandemic Planning Scenarios, “The planning scenarios are
being used by mathematical modelers throughout the Federal government. … The planning scenarios may also be useful to hospital administrators in assessing resource needs.”1 3 5
The CDC IFR estimate is slightly less than half the 0.9 percent estimate provided by an Imperial College London model published on Mar. 16, 2020 that forecast as many as 2.2 million deaths in the U.S. and significantly less than the 1-2 percent estimate given in March by Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases (NIAID).4 7 8 9 10
The CDC’s 0.4 percent rate, however, is for those who show symptoms of COVID-19. The CDC estimates that 35 percent of people who are infected with the SARS-CoV-2 virus never develop symptoms of the disease, which means that the IFR for the virus is 0.26 percent.1 2 3 4 That would place the fatality rate for the SARS-CoV-2 virus just slightly higher than that of seasonal influenza, which is estimated at 0.1 percent.8 9 10
In April, studies conducted by Stanford University and the University of Southern California estimated the IFR for COVID-19 at 0.1 percent to 0.2 percent, which places the rate in the same range at the new CDC rate. Both studies were criticized for underestimating the fatality rate for the disease. The CDC rate is now also attracting similar criticism.11 12
A study published in early May in Health Affairs by a professor at the University of Washington, Anirban Basu, estimated the COVID-19 symptomatic infection mortality rate in the U.S. to be 1.3 percent.13 Using data through Apr. 20, 2020, Professor Basu said that county-specific infection morality rates likely varied between 0.5 to 3.6 percent and that, “The overall IFR for COVID-19 should be lower when we account for cases that remain and recover without symptoms.”
Commenting on the CDC’s estimated 0.26 COVID-19 fatality rate, epidemiologist William Hanage, PhD of Harvard University’s T.H. Chan School of Public Health said, “If you’re taking these numbers to be your guide, they’re obviously lowball estimates.” Epidemiologist Joseph Lewnard, PhD agrees that the CDC’s fatality rates are “certainly at the very low end.5
“Greater clarity on the scientific basis for these estimates is urgently needed,” Dr. Lewnard said.5
In a recent analysis, Stanford epidemiologist John Ioannidis, MD estimated the IFR for COVID-19 at between 0.02 percent and 0.4 percent. “While COVID-19 is a formidable threat, the fact that its IFR is much lower than originally feared is a welcome piece of evidence,” wrote Dr. Ioannidis. “At a very broad, bird’s eye view level, worldwide the IFR of COVID-19 this season may be in the same ballpark as the IFR of influenza.”14 15
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