Due to the currently very high corona numbers, many people are increasingly concerned about testing positive before an exam, as they will then not be able to take part in it.
In the worst case, this can delay ones studies for a semester.
If this happens and you are in quarantine due to a Corona infection, according to the current Corona statutes (see §4 (4) here) you have the possibility of an alternative date to make up for the exam this semester.
If you are affected by this, simply contact your lecturer. If there are problems, simply contact the dean’s office of your faculty (Med, ReWi, Phil, Nat, Tech), they have been sensitised to the issue and will solve the problem with you.
So please get tested and stay at home if you are positive/sick so as not to endanger other people – there is always a solution.