Reply #44: Your table shows infection rates in Baltimore and 4 other cities

[muriel_volestrangler]

Note that the total tested was higher in Baltimore than the other cities, despite it being far smaller that NYC or LA (and it won't have such aare larger proportion of MSM in the population that it could make up for that in any way). You can't take the total number of HIV cases found and imply anything from it for the country as a whole. Just weight the figures for those 5 cities acccording to their total popluation and you'll get a prevalence of under 20%.

In contrast, the CDC figures that dsc linked to, which are in this page too, say:

HIV prevalence in males >= 13 in the whole US: 828,000 = 685.7 per 100,000 (ie total males for that age group = 120 million)
Of the 828,000, 532,000 came from male-to-male sexual contact, and 54,900 from MSM or injection drug use when it can't be determined which it was.

Note that these figures include undiagnosed HIV - the page says " CDC now estimates that 1.1 million adults and adolescents (prevalence rate: 447.8 per 100,000 population) were living with diagnosed or undiagnosed HIV infection in the United States at the end of 2006" and "an estimated 232,700 (21.0%) persons living with HIV infection had not been diagnosed as of the end of 2006".

If we use a 6% figure for MSM out of the total male adolescent/adult population, then it's
(532,000+54,900)/(.06*120,000,000) = 8% of MSM who are HIV positive.

That';s using teh CDC figures for the whole country, which are designed to be used together. The one thing they don't do is estimate the proportion of MSM in the general population; they note a 3.7% figure for ever having male anal sex among 15-44 year olds. Even if we drop the overall proportion of MSM to that, we get 13%.