Of those, 20% had undiagnosed HIV infections. (Center for Disease Control, cdc.gov/hiv/topics/surveillance/basic.htm#exposure)Percentage of Homosexual Infected is much higher than non homosexual Population.2% of U.S. population is gay has largest % of HIV infection: Gay, bisexual, and other men who have sex with men (MSM) represent approximately 2% of the US population, yet are the population