I hear/see a lot of numbers put forth about the Covid 19 virus. The one I have some trouble with is the reported death rate. It has been suggested that the death rate is around 1.3% (about 4 times worse that the flu). I get that, but I don't think most people understand just how the flu numbers are generated. It goes like this: Laboratory-confirmed influenza-associated hospitalization rates are obtained from the Influenza Hospitalization Surveillance Network (FluSurv-NET), a collaboration between CDC, the Emerging Infections Program Network, and selected state and local health departments in 13 geographically distributed areas in the United States that conduct population-based surveillance. The network includes hospitals that serve roughly 9% of the U.S. population. The reported numbers of hospitalizations are used to calculate hospitalization rates and the rates are adjusted to correct for under-detection of influenza. This adjustment is done by using the percent of persons hospitalized with respiratory illness who were tested for influenza and the average sensitivity of influenza tests used in the participating FluSurv-NET hospitals. The data on influenza testing can lag up to two years after the end of the season, so for more recent seasons, testing data from prior seasons is used. (From the CDC website). Okay, to sum it up the CDC uses a mathematical model to estimate the numbers of influenza illnesses, medical visits, hospitalizations, and deaths in the United States. HANG IN THERE MY RANT IS ALMOST OVER. Now look at how the Covid 19 death rate was reported back on March 3rd: Total number of confirmed case (90,893) divided by the total number of deaths (3,110) That gives you a death rate of 3.42% Problem is this number is not accurate since your not using the same type of model. This< I believe is more accurate:
Dr. Toni Ho, a consultant in infectious diseases at the Medical Research Council (MRC)–University of Glasgow Centre for Virus Research, U.K., echoes similar sentiments.
She goes on to suggest that the figure of 3.4% is likely an exaggeration, mainly due to the challenges of calculating mortality rates outlined above.
“The quoted mortality rate of 3.4% is taken from confirmed deaths over total reported cases. This is likely an overestimate, as a number of countries, such as the United States (112 confirmed, 10 deaths) and Iran (2,336 cases, 77 deaths), have had limited testing. Hence, few of the mild cases have been picked up, and [the total number of cases] we are observing is the tip of the iceberg.”
In fact, the overestimation could be 10 times higher than the reality, notes Mark Woolhouse, a professor of infectious disease epidemiology at the University of Edinburgh, U.K.
“f a significant number of mild cases have been missed or not reported, then this [3.4%] estimate is too high.”
“Though there is disagreement about this, some studies have suggested that it is approximately 10 times too high. This would bring the death rate in line with some strains of influenza.”
– Prof. Mark Woolhouse