"Mixup" joke
A woman went to the doctor's office for a physical. The doctor took a blood sample and told her to return in one week for the results.
One week later, she and her husband returned to the doctor's office. The doctor took the husband aside and told him, "Sir, I'm afraid I have some bad news. We accidentally mixed your wife's blood sample with another patient's, and we have no idea whose is whose. The bad news is one has Alzheimer's disease, and the other has AIDS. I want you to come back in another week and by then I should have it all sorted out."
The man looked scared and said, "That's terrible, doc, what should I do until then?"
"Well, when you're driving home today, drop her off two blocks away from your house. If she makes it home, don't have sex with her!"
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