Depends what you means with "tested positive" because the most common assessment is the PCR with > 40 cycles which is a bogus test and gives mostly false positives.
Fiancee tested positive after I went on my first flight in two years to onboard for a new job. I didn't but had mild symptoms after getting back. Took the opportunity to get a booster when it wouldn't induce a lot of side effects since my immune system is revved up already.