[dp0622]

Now THAT makes sense.

But doesn’t that inherently taint the study?

How much the virus progresses and how bad it affects each group would be, I think, important aspects of the study.

Treating those who show infection will taint those results very much, no?

[Hiddigeigei]

Treating those who show infection will taint those results very much, no?
It depends on whether the study is designed to see if the treatment protects against infection or severity of illness after infection. If the subject is young and healthy, there's a good chance he/she isn't going to show severe symptoms anyway.