CDC says 35% of coronavirus infections are asymptomatic
In new guidance for mathematical modelers and public health officials, the US Centers for Disease Control and Prevention is estimating that about a third of coronavirus infections are asymptomatic.
The CDC also says its “best estimate” is that 0.4% of people who show symptoms and have Covid-19 will die, and the agency estimates that 40% of coronavirus transmission is occurring before people feel sick.
For people age 65 and older, the CDC puts that number at 1.3%. For people 49 and under, the agency estimated that 0.05% of symptomatic people will die.
One expert quickly pushed back on the CDC’s estimates.
“While most of these numbers are reasonable, the mortality rates shade far too low,” biologist Carl Bergstrom of the University of Washington told CNN.
Bergstrom, an expert in modeling and computer simulations, said the numbers seemed inconsistent with real-world findings.
“Estimates of the numbers infected in places like NYC are way out of line with these estimates. Let us remember that the number of deaths in NYC right now are far more than we would expect if every adult and child in the city had been infected with a flu-like virus. This is not the flu. It is COVID,” Bergstrom said.
“As I see it, the ’best estimate’ is extremely optimistic, and the ’worst case’ scenario is fairly optimistic even as a best estimate. One certainly wants to consider worse scenarios,” Bergstrom said of CDC’s numbers.