heech said:
...the risk of HIV transmission for protected partners (especially with HIV+ partners on regular meds, and with low viral load) is low... not dramatically different from pre-med students that might be engaging in promiscious, unprotected sex.
LVDoc has already addressed the USA vs World statistics, discrepency, but the above quote is even more bothersome to me because it is just inaccurate.
Using the data calculated earlier, a the chances of an HIV+ male transmitting to a HIV- female in a normal, protected sexual relationship over 5 years is roughly 4.5%.
That is assuming that 100% of all the female's sexual partners are HIV+. National data estimates that 0.6% of the American adult population is HIV+, knowingly or unknowingly. (
http://www.avert.org/aids-america.htm). Assuming the average female is having roughly the same amount of sex as the one in the committed relationship, and all of it is protected, she is slightly less than
200 times less likely to get HIV in any given period of time than the woman in a committed relationship to an HIV positive male. Or, she has a .0225% chance of becoming infected with normal, frequent, protected sex.
You specifically said "unprotected sex," so let's figure out those chances. If the infection rate for a woman who is having 100% of her sexual encounters with HIV+ men and they're unprotected is 6.8 per 100 years, you can say she has a 34% chance of infection in 5 years. For the average woman who is having 0.6% of her encounters with HIV+ men, this makes for a .17% chance of becoming infected in 5 years.
So, a female having protected sex exclusively with an HIV positive man has a 4.5% chance of becoming infected in 5 years. A female having the same amount of sex, only all unprotected, with the general populace has a 0.17% chance of becoming infected in 5 years. In other words,
the OP's friend having protected sex is 26.5 times more likely to become infected with HIV than is a normal female having unprotected sex.
Many of the assumptions that I made are clearly a stretch (e.g. a single person has as much sex as a woman in a committed relationship over a 5 year span as well as how the 0.6% of the populace would break down), but the difference between reality and my assumptions usually only widens the gap. This means that the 26.5 figure is probably quite a bit lower than the actual figure.
Also, for those that might not have read the entire thread, I'm only talking about male to female transmission because that's the scenario in the OP, not for any sexist motives. The numbers could easily be done for female to male using the data in the abstract on pg 2 of this thread.