It happens way too often. For shows with a long tech week and/or long runs, when it’s all over I get a cold.
I have heard of brides getting sick on their honeymoon because the stress from the wedding is gone. The stress kept the viruses at bay and when it is gone you are left weakened from all that you have done and more susceptible to infection.
This has to be what happens to me. It just stinks that once I’m done with a show and can start taking more classes again and working on my technique, I have to take time off because I have a cold 😦