Pandemic Death Rate Calculation

The true number of infections is estimated to be at least four times, and possibly five to ten times, larger than confirmed tested cases, based on patterns from other epidemics. Treating the confirmed-case fatality rate as the true fatality rate for all infected people is a mistake, because early confirmed groups are biased toward people sick enough to be tested. Early pandemic death-rate figures are unstable because the denominator is especially uncertain due to infections invisible to testing systems. A reported pandemic fatality percentage is not a fixed truth about a virus; it depends on whether deaths are divided by confirmed tested cases, estimated true infections, or the entire population. The same number of deaths can represent vastly different fatality rates depending on the denominator chosen — for example, 5 deaths out of 100 confirmed cases is 5%, but 5 deaths out of 10,000 true infections is 0.05%. Dividing deaths by confirmed tested cases produces an artificially small denominator, making the resulting percentage appear higher than the true infection fatality rate.