An Omicron oddity: The number of cases doesn’t predict the number of deaths

Early in the Covid-19 pandemic, the case fatality rate was frightening. This metric represents the proportion of all known people infected with a disease who die from it. The World Health Organization initially put it as high as nearly 16% in Algeria.

Several colleagues and I at Vital Transformation began closely following the data on Covid-19 early in the pandemic. We wondered if case fatality rates might be skewed by lack of testing. We collected data on various indictors that early on were thought to be influencing the spread of Covid-19.

We analyzed standard metrics such as case rates weighted by age and population densities, but also deeper metrics such as tourists per year and the number of university students in a city. Our findings, published in April 2020, showed that the case fatality rate was indeed being widely overstated and predicted that it would drop by 5% for every 10% increase in the number of tests.

That prediction turned out to be correct, as it is now known that the majority of early Covid-19 cases, particularly in those under age 65, had been completely missed. The overall infection fatality rate, the actual measure of deaths due to the overall rate of infection across the entire population obtained via genetic testing, is closer to 0.2%, or two deaths per every thousand people infected.