Suppose Bob has symptoms and suspects he has COVID-19. He decides to get tested. While out and about, he decides to enter a store and pick up some groceries.

How wrong is this?

Suppose someone else gets infected as a result and dies. Or suppose someone just suffers significantly for a couple of weeks. Or suppose someone is financially ruined by the resulting medical bills.

Is Bob responsible? Is he potentially guilty of killing someone?

If I were to punch someone at random in the store, I might well get arrested and charged with a crime. Bob does far more harm, but won't get arrested. I tend to think that if Bob believes himself infected and he exposes others knowing this, he should be held responsible. The consequences are far worse than punching someone. And the infection is likely to spread from those he infects to still more others, maybe hundreds.

Many people have a lax attitude about exposing people to their illness. I've had friends invite me over when they knew they were sick with flu and in at least one case, I got the flu and suffered terribly for two weeks. This "friend" thought nothing of exposing me, the asshole! The result was far worse than if he had punched me. And yet our culture is such that if I get very angry about this, I'm seen as unreasonable.

It's nobody's fault. I didn't get sick or infect you intentionally. The virus did it, not me.

How much less suffering would there be if we all were to automatically quarantine ourselves upon suspecting ourselves of being infected with anything contagious?