Coronavirus’ “infection fatality rate (IFR)” based mortality rate for the United States is as low as 0.5%. Proponents of IFR are of the opinion that it is a more realistic measure in comparison to the “case fatality rate (CFR)”. However, CFR is the more widely used measure. Moreover, on the basis of commonly used CFR, the mortality rate for COVID-19 ranges between 1 to 5%.
Coronavirus: Decoding the medical jargon
IFR is a ratio of total deaths to the number of infected individuals. IFR is considered a more appropriate measure because it attempts to also account for undiagnosed and asymptomatic infections. On the contrary, CFR is a ratio of total deaths to the number of diagnosed cases.
.26% IFR means 4,303,846 people in NJ have been infected with Coronavirus, almost exactly 50% of the state. Do you believe that’s the case?
— K O (@kate10010) May 26, 2020
Studies that used IFR also found that COVID-19, although more common, is not as deadly as currently thought. These studies also discovered that a large proportion of people infected with COVID-19 in the US never became critically ill. Therefore, some doctors suggest that Coronavirus appears much less dangerous upon inclusion of these mild cases of infection in the statistics.
Coronavirus: Interpretation of the metrics
“The current best estimates for the infection fatality risk are between 0.5% and 1%,” said Dr. Caitlin Rivers, as quoted by NPR. Dr. Caitlin is an epidemiologist at the Johns Hopkins Center for Health Security.
First, the IFR for covid is .26. for anyone under 50 it's at or less than flu level risk. It's not dangerous for most of the population.
2nd, from serological studies we are mich further along than we thought.
3rd we may have some from exposure to previous coronavirus colds. pic.twitter.com/RsXg5r3F2X
— Polish Bandit (@bandit_polish) May 25, 2020
Dr. Caitlin further added that even a 1% fatality rate for Coronavirus is considered a formidable threat. She explained that this % is still “many times more deadly than the seasonal Influenza.”
The U.S. Centers for Disease Control and Prevention (CDC) reported 34,200 deaths from Influenza in the 2018-19 flu season. In addition, Influenza infected over 35.5 million Americans. The flu season in the U.S. starts in fall, and lasts for an average of 13 weeks.