Have you seen these two recent meta-analysis of HIV transmission rates? Comparing them to your numbers, it seems that Wikipedia/CDC have greatly understated the risk for P/A sex acts (due to using older studies?).
Also, according to this page, the transmission rates for genital herpes are similar to HIV for P/V sex acts, so AIDS is not the only STD to have such low transmission rates.
it would still require an unrealistic initial foothold in the population by other means before it could ever spread sexually
I think the conventional theory is that HIV established an initial foothold by means such as needle sharing, blood transfusions, and P/A sex acts. That seems quite realistic to me. Why do you think it's unrealistic?
No I haven't seen them until now. I haven't really been looking into or thinking about this until just recently.
I originally quoted the wikipedia data, which several us tracked down and analyzed in another thread (it comes from the CDC and originally from a single medium-ish European study which I think did a fairly good job to control for factors such as condom use and what not given the complexities):
...It is claimed that HIV is a sexually transmitted disease. However, the typical estimates of transmission rate are extremely low: 0.05% / 0.1% per inserti
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