thanks. so I should just not be fingered by semen/ejaculate as a precaution? I know you said it's theoritical, but still, I don;t want to be reckless
You had accurate responses from Teak on the HIV community forum. As he told you--and you said you understood--just because HIV can be found in a particular body fluid doesn't mean that there is risk of transmission, especially from exposures that don't introduce that fluid (in substantial amounts) directly inside the body.
To the specific questions:
1) Yes, the virus dies rapidly on drying. But even when it persists, it cannot necessarily be transmitted.
2) I'm not sure what word was bleeped, but most likely it was the 3-letter word for semen. Any risk is theoretical, with no known infections by that route. But it could occur if a finger wet with HIV infected semen were inserted into a person's vagina or rectum.
3) The common "lifestyles" that confer high HIV risk in North America and most western countries are injection drug use, commercial sex (or frequent sex with commercial partners), and sex between men.
4) Using condoms is highly protective, but not 100%. Some apparent condom failures might occur because of the sorts of exposures you ask about. But they are rare.
When no data exist, "maybe", "low risk", "probably not", and similar statements are all that is possible. For many such kinds of events, you can expect there will never be definitive data, only the best judgment of experts. That's just the way it is. Suck it up.
As I said above, avoid partners with obvious risky lifestyles, and use condoms for insertive vaginal and anal sex. Otherwise, forget HIV. You're never going to catch it.
Best wishes-- HHH, MD