> He knew the risks that he could possibly be infected 
   > and decided to endanger others when he could have 
   > easily stayed home

That may be over stating things. Given that he is a doctor, and he is confident in his process with keeping clean, he might actually have a really hard time believing that he was infected. People have faith in their own abilities, that lets them do things which might put them at grave risk.

In the military service you will hear it as "trust in your training." Basically you believe you won't be the guy that gets shot or steps on a land mine or what ever because you trained really hard and you know you are implementing that training flawlessly.

It is entirely possible this person was so confident in their training, and their own competence in putting that training into action, that they believed it was impossible for them to be infected. They do the self monitoring because that is what you are supposed to do, but it never comes up positive because you did what you were supposed to do. This gets worse the more times you do something and the outcome is exactly as you expect it to be.

So I can believe this guy didn't believe he was at risk. Just like I have foolishly believed this small change I am checking in can't break anything[1]. One hopes he was asymptomatic when he went out. Unlike the guy in Texas who was showing symptoms and went home, or the nurse who had a fever and got on a plane anyway.

Sure you could put anyone coming back from West Africa in an airstream trailer [2] for 21 days but that is impractical if you want to support the process of fighting it in West Africa.

[1] I know, hugely different scale, but illustrative of my fight against my own assumptions in the pursuit of better process.

[2] http://en.wikipedia.org/wiki/Mobile_Quarantine_Facility#medi...