smallpox had affected the human population for three millennia, infecting the young, the old, the rich, the poor, the weak and the resilient.
Spread by a cough or sneeze, smallpox caused deadly rashes, lesions, high fevers and painful headaches – and killed up to 30% of its victims, while leaving some of its survivors blind or disfigured.
An estimated 300 million people died from smallpox in the 20th century alone, and more than half a million died every year before the launch of the global eradication programme.
http://polioeradication.org/news-post/the-world-without-vaccines/
We're simply not able to increase our testing capacity as quickly as the number of cases rises. Then two things will coincide: First, some of the people who are now sick with COVID-19 will die. And second, because we won't be able to test everyone, our statistics will be incomplete. Our fatality rate will then also rise. It will appear that the virus has become more dangerous, but this will be a statistical artifact, a distortion. It will simply reflect what's already starting to happen: We're missing more and more infections.
ZEIT ONLINE: What can we do about it?
Drosten: We have to take shortcuts. If one person in a household tests positive, we could, for instance, consider the entire household to be positive, even without a test. Because we know that is what is going to happen: If one family member gets infected, they infect everyone else. If you say right away that the entire family is positive, you save yourself a lot of testing. Imagine that you're infected, and the next day your wife has to go and stand in line. And then imagine the test doesn't detect her infection yet, and she has to come back. That doesn't make any sense. So, it's better if the entire family isolates at home from the get-go. They're already doing this in the Netherlands and I'm going to suggest that Germany follow suit in discussions with health authorities.
https://www.zeit.de/wissen/gesundheit/2020-03/christian-drosten-coronavirus-pandemic-germany-virologist-charite