1) I like public toilet water splashing up into my anus
2) I want to relay scientific facts about the transmissibility about a disease that has a lot of fear, stigma, and falsehoods spread about it, often in the service of an anti-gay agenda.
To answer what you don't know: no, splashback can't transfer HIV.
It's virtually impossible for HIV, you're time would be better spent planning how to spend your big lottery win. The reason anal sex is better at spreading HIV is because anal tearing allows it into the bloodstream, apart from that your anus is no different from your ass checks, you're arm or anywhere else.
Doesn't stuff in your intestines get naturally absorbed into your bloodstream by some mechanism? I always figured the danger with putting things in your ass was that you would bypass the safety mechanism that the stomach acids double as.
Getting from the toilet through the anus and into the intestines is it's own challenge. There's shit, multiple sphincters and bends in the way.
Then you've got the transmissibility of aids itself, which is actually quite low for anything other than blood transfusions: http://www.aidsmap.com/Estimated-risk-per-exposure/page/1324...
Put all that together and there's no chance anyone got aids from toilet splashback.
Downvoted for focusing on generating a disgust reaction instead of being aware of any scientific facts.