If you really believe your illness is a result of flying with another pilot who came to work sick...please call Pro Stans. You will be doing everyone a favor.

As for the OP question. Just forget about it. If you are sick, mark off sick. You will not be disciplined...period. Not at this airline.

OTOH! If you show up sick on my trip, I will handle it for you and that will not be pleasant. ( I actually had to do this once with a FA.)

Every employee has the right to a safe work environment.