Coronavirus (COVID-19)

There are several sources reporting the absolute number of cases in different countries. However, I could not find nicely prepared data on (a) the percentage of the infected population per country, and (b) the daily percentual increase per country. So I have composed some statistics about the spread of the coronavirus (COVID-19).

Percentage of population infected

The following graph shows the number of coronavirus cases (COVID-19) relative to the size of the population in percent (per country). This statistic counts everybody who has been infected independent (and possibly recovered).

This graph shows that currently South Korea and Italy are the worst hit countries with more than 0.01% of their population having been infected.

Daily increase

The following figure depicts the daily increase of the number of infections in percent of the confirmed (and possibly recovered) cases. To make the graphs a bit more smooth, we display the average value of the last 3 days. Intuitively, a value of 100% means that the number of confirmed infections has doubled that day.

The current daily increase in infections is above 25% in most European countries and the United States. At this speed, the number of infection multiply by 10 within 10 days.

Why is the new coronavirus dangerous

There several reasons that the new coronavirus is more dangerous than the seasonal flu:

Mortality rate:

  • The seasonal flu has a mortality rate of 0.1%.
  • The new coronavirus has a 35 times higher mortality rate of 3.5%.

Lack of vaccinations:

  • For the seasonal flu there are vaccinations. The vaccinations protect risk groups and they create a herd immunity that slows down the virus spread.
  • For the new coronavirus, vaccines will be available at earliest in 2021.

I am in a low risk group, why should I care? Indeed, the mortality risk is much lower for young adults (and even lower for children). However, everybody should care to protect those less fortunate who are part of the high risk groups. This concerns elderly, but also young people with chronic illnesses. Moreover, the low risk group still runs a mortality risk of 0.1%. Would you voluntarily play Russian roulette with these odds?


Please do not take the next graph for a serious forecast. The next graph shows the future infection spread (the percentage of infected population) under the assumption that the daily increase will not slow down. The purpose of this graph is to show how important it is that the containment efforts are increased.

Death toll

The expected death toll in various regions:

  • Europe: 17,100,000
  • United States: 7,600,000
  • Japan: 2,900,000
  • Germany: 1,900,000
  • Iran: 1,900,000
  • France: 1,500,000
  • United Kingdom: 1,500,000
  • Italy: 1,300,000
  • South Korea: 1,100,000
  • Spain: 1,000,000
  • Netherlands: 300,000
  • Belgium: 200,000
  • Sweden: 200,000
  • Norway: 100,000
  • Hong Kong: 100,000
  • Singapore: 100,000
  • Switzerland: 100,000

How are these numbers derived? According to Christian Drosten, the head of the virology department at Berlin’s Charité clinics, two thirds of the population need to be immune for the virus to stop spreading. Europe has a population of 741 million. Thus 488 million need to get the virus before it stops spreading. Assuming a mortality rate of 3.5%, this amounts to 17 million deaths in Europe caused by COVID-19. One may argue whether the actual mortality rate is lower due to high medical standards in Europe. However, if the virus keeps spreading at current speeds, then hospitals will be hopelessly overloaded.