Men who have sex with men (MSM) become HIV positive at a rate more than 50 times that of women or straight men, according to new statistics from the Centers for Disease Control and Prevention (CDC) and reported by RH Reality Check. The CDC's Amy Lansky, PhD, announced the statistics last week during a plenary session at the 2009 National HIV Prevention Conference in Atlanta.

While the CDC's incidence estimates released last year showed that MSM account for 50 percent of new HIV cases, new data reveal the actual rates of HIV prevalence in this group as opposed to raw numbers. In 2007, there were 692.2 new HIV cases per 100,000 MSM. Coupling this rate with the raw numbers allows researchers to better compare HIV risk in MSM with other populations.

To arrive at the rate of infection, the CDC used 4 percent to represent the proportion of adolescent and adult men who acknowledge having had sex with another man in the past five years. That percentage is a median estimate based on other surveys and reports.