A new study published in The Lancet Infectious Diseases medical journal estimates that the death rate of coronavirus is significantly lower than previously reported.
In early March, World Health Organization Director-General Tedros Adhanom Ghebreyesus said the estimated mortality rate of COVID-19 globally was about 3.4%, while Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said it could be anywhere from 1-2% if “you just do the math,” based on initial reports out of other countries.
“What we’re hearing right now, on a recent call from the WHO this morning is that there aren’t as many asymptotic cases as we think. Which made them elevate, I think, what their mortality is,” Fauci explained in the first week of March. “You know as well as anybody that the mortality for seasonal flu is .1% so even if it goes down to 1% it’s still 10 times more fatal.”
As reported by CNN Tuesday, a new study published in Lancet estimates that even the lower-end 1% fatality rate estimation is too high. A more accurate estimation of the percentage of people who will die due to complications from the virus, researchers say, is about two-thirds that, 0.66%.
“That coronavirus death rate, which is lower than earlier estimates, takes into account potentially milder cases that often go undiagnosed — but it’s still far higher than the 0.1% of people who are killed by the flu,” CNN explains. “When undetected infections aren’t taken into account, the Lancet study found that the coronavirus death rate was 1.38%, which is more consistent with earlier reports.”
As noted by CNN, when Dr. Fauci presented his 2% estimation in March, he stressed that determining the true death rate requires accurate data on the number of people who have contracted the virus but are asymptomatic, or show no symptoms, a metric that has been glaringly lacking thus far. Only taking into account confirmed cases results in an incomplete data set and generally includes those with the more severe symptoms, rather than the more mild cases, which some previous studies suggest could be about half the number of COVID-19 cases.
The new study attempts to account for the asymptomatic or very mild cases, not just the confirmed cases. To do so, the researchers looked at infection rates of people who returned to their home countries on flights from Wuhan, China, CNN explains.
“According to the study, these people received PCR tests — a type of test that would be able to identify how many of those travelers were shedding the virus, even if they didn’t show symptoms,” CNN explains. “Researchers combined that data on ‘infection prevalence’ with public information on reported cases and deaths, estimating the overall death rate to be about two-thirds of 1%.”
For those younger than 40, the estimated fatality rate is even lower, just 0.16%, while those younger than 9 have only an estimated 0.00161% chance of dying from complications related to the virus. For those 80 or older, however, the fatality rate is an alarming 7.8%, researchers found.
“There might be outlying cases that get a lot of media attention, but our analysis very clearly shows that at aged 50 and over, hospitalisation is much more likely than in those under 50, and a greater proportion of cases are likely to be fatal,” said Imperial College London professor and study co-author Azra Ghani said, as reported by CNN.
While researchers found that the fatality rate is far lower than some previous estimates, they also note that the often prolonged recovery time for the virus, which can take over three weeks, threatens to overwhelm health care systems.