NEW YORK (November 27, 2012)—One in 5 new HIV infections occur in a tiny segment of the population, young men who are gay or bisexual, the U.S. Centers for Disease Control and Prevention reported Tuesday.

The CDC released new numbers that spotlight how the spread of the AIDS virus is heavily concentrated in young males who have sex with other males.

Only about a quarter of new infections in the 13- to 24-age group are from injecting drugs or heterosexual sex.

The Centers for Disease Control and Prevention said blacks represented more than half of new infections in youths.

The estimates are based on 2010 figures.

Overall, new U.S. HIV infections have held steady at around 50,000 annually.

About 12,000 are in teens and young adults, and most youth with HIV haven't been tested.