Your numbers are right but
[QUOTE=Neurosynth;2172961]There should be a sticky post or something with the STD probabilities, because this seems to be a recurring question. Some of the following repeats what I've posted before. Yes, I'm only addressing HIV here. It is by far the most common *fatal* STD that can't be cured, but only controlled. But the principles below can be used with other diseases too if you look up the base statistics.
In that regard what seems to be often forgotten is that you have to multiply the probability of transmission with the probability of encountering an infected partner. That calculation significantly lowers the overall probability.
HIV rate among female German sex workers = 0. 2% or 0. 002 (20 in 10,000).
See page 14: [URL]https://ecdc.europa.eu/sites/portal/files/media/en/publications/Publications/dublin-declaration-sex-workers.pdf[/URL].
HIV transmission rate for vaginal sex, female to male = 0. 04% or 0. 0004 (4 in 10,000).
[URL]https://www.cdc.gov/hiv/risk/estimates/riskbehaviors.html[/URL]
The probability of becoming infected via vaginal sex with a random sex worker in Germany.
= 0. 002 * 0. 0004 = 0. 0000008 = 0. 00008% (8 in 1,000,000).
To put that in perspective it's more likely you could flip a coin and get 20 heads in a row than contract HIV from a random sex worker in Germany.
Put another way, if you had vaginal sex every day for 20 years with a different random sex worker in Germany your probability of HIV infection would be 0. 00584.[/QUOTE]The probability calculations you have here are totally sound but not for all venues.
In an AO club, maybe the 0. 2% is more like 2. 0%, very low but higher than 0. 2%, or maybe lower since only streetwalkers come in higher than 0. 2%, not sure.
In a prominent FKK it is far lower than 0. 2%. But that 0. 2% assumption depends on the base, actually I would not be surprised if the AO clubs come in lower than 0. 2% for HIV. But if you are approach an IV drug using steetwalker than that is probably higher than the 0. 2% base, maybe all Sauna clubs are lower.
The risk is of course quite low, but while I am happy with BBBJ, I do not practice uncovered vaginal or anal sex, just because I have from my point of view, total peace of mind, I also have never contracted anything from BBBJ in over 10 years of receiving BBBJ, approx 100 times a year for a decade.
I would be more worried about that nasty strain of gonorrhea than HIV.