AIDS Patient Care and STDs:: "The District of Columbia (DC) has among the highest HIV/AIDS rates in the United States, with 3.2% of the population and 7.1% of black men living with HIV/AIDS. ... Of 500 MSM, 35.6% were black. Of all men, 14.1% were confirmed HIV positive; 41.8% of these were newly identified HIV positive. Black men (26.0%) were more likely to be HIV positive than white (7.9%) or Latino/Asian/other (6.5%) men (p<0.001). Black men had fewer male sex partners than non-black, fewer had ever engaged in intentional unprotected anal sex, and more used condoms at last anal sex. Black men were less likely to have health insurance, have been tested for HIV, and disclose MSM status to health care providers. Despite significantly higher HIV/AIDS rates, black MSM in DC reported fewer sexual risks than non-black. These findings suggest that among black MSM, the primary risk of HIV infection results from nontraditional sexual risk factors, and may include barriers to disclosing MSM status and HIV testing. There remains a critical need for more information regarding reasons for elevated HIV among black MSM in order to inform prevention programming."
Comment: Another possibility is that Africans and African Americans may be more susceptible to HIV infection than whites, due to genetic differences. For example, the double CCR5 deletion mutation, which gives almost complete immunity to HIV, occurs in about 1% of whites but 0% of Africans. (The single CCR5 deletion, associated with slower HIV progression, occurs in more whites; it might further reduce the infection rate.) Such genetic differences could lead to higher HIV prevalence in one population than another, despite less behavioral risk.
But for another theory, see Higher HIV rates among black MSM in the US may be linked to attitudes about homosexuality.