The CDC also says that the “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 occurs before humans feel sick.
The agency warns that these numbers are subject to change as more is learned about Covid-19 and warns that the information is intended for planning. However, the agency says its estimates are based on real data collected by the agency before April 29.
The numbers are part of five planning scenarios that are “used by mathematical modelers within the federal government,” according to the CDC. Four of these scenarios represent the “lower and upper limits of disease severity and virus transmission”
The fifth scenario is the CDC’s “current best estimate of virus transmission and disease severity in the United States.” In this scenario, the agency describes its estimate that 0.4% of people who feel sick with Covid-19 will die.
For people aged 65 and over, the CDC puts this number at 1.3%. For people under the age of 49, the agency estimates that 0.05% of symptomatic people will die.
The expert pushes back
In the worst-case scenario, not the Agency’s “best estimate,” the CDC lists a symptom death rate of 0.01, meaning that 1% of people with Covid-19 and symptoms will die.
In the least severe scenario, the CDC puts this number at 0.2%.
One expert quickly turned to the CDC’s assessments.
“While most of these numbers are reasonable, mortality is too low,” University of Washington biologist Carl Bergstrom told CNN.
Bergstrom, an expert in modeling and computer simulations, said the figures seemed inconsistent with real-world findings.
“Estimates of the number of people infected in places like New York are out of line with these estimates. Let’s remember that the number of deaths in New York at the moment is much higher than we would expect if every adult and child in the city was infected with a flu-like virus. This is not the flu. This is COVID, “Bergstrom said.
“As I see it, the ‘best estimate’ is extremely optimistic, and the ‘worst case’ scenario is quite optimistic even as a best estimate. One certainly wants to consider worse scenarios,” Bergstrom said of the issue. CDC.
“By introducing these as a formal set of parameters for modeling efforts, the CDC influences models produced by federal agencies, but also the wider scientific discourse, because there will be some pressure to use standard CDC parameter sets in modeling documents ahead. “he said I said.
“Given that these parameters determine the underestimation of mortality by a significant margin compared to the current scientific consensus, this is deeply problematic.”
The numbers are for planning, says the CDC
“The scenarios are designed to improve public health preparedness and planning. They are not predictions or projections of the expected impact of COVID-19,” the CDC said.
It says the figures do not “reflect the impact of any changes in behavior, social distancing or other interventions” that would be relevant to some of the agency’s assessments – such as how many infections result from each case.
However, the CDC characterizes the numbers as preliminary estimates by federal agencies, including the CDC and the HHS Office of the Assistant Secretary for Preparation and Response, which are “designed to help inform the decisions of modelers and public health officials who use mathematical modeling.” “
According to the best-case scenario, the guidelines say that 3.4% of symptomatic people with Covid-19 will need to be hospitalized, rising to 7.4% in people aged 65 and over. The CDC also says it suggests that people without symptoms are just as infectious as those with symptoms.