Earlier quoted context omitted.
Buggery. It's been illegal many places for a very long time because it spreads disease. The sodomy laws were effectively repealed and we got AIDS. It was not a coincidence.
Sexual intercourse of any kind spreads disease. AIDS didn't become an epidemic because of anal intercourse. It's pretty clear that AIDS and other sexually transmitted diseases spread just as well from almost any kind sexual activity, and many of them -- including AIDS -- spread from any transfer of bodily fluids at all. Going further, I'd wager that any form of interpersonal contact, even non-sexual, is as likely to…
It's clear that HIV can spread via a wide range of sexual activities, but some are much higher risk than others. At the extremes, receptive anal intercourse has a transmission risk roughly 50 times higher than insertive vaginal intercourse, while the risk of oral sex is believed to be non-zero but too low to be accurately measurable.