With the sex you described HIV would only pass when you had sex 6 years ago with the unprotected anal sex and giving a blow job. The chances for HIV passing would be much greater with the unprotected anal sex when compared to giving the blow job.
For there to be any chance the person has to be HIV positive. The only problem is that many people do not know their status since HIV often does not cause any symptoms and it could be sometime since they last tested.
We don’t see HIV being passed when receiving oral sex, but there are a few STI that can be passed that way like gonorrhea and syphilis. Have a look at our “Know your chances” web page, it provides information on your chances of getting or passing an STI depending on how you are having sex.
I would recommend going for an STI test. Have a look at our “STIs at a glance” chart, it provides information on how long you need to wait before getting tested (window period).
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