Young gay men who booze it up before sex, enjoy multiple sex partners and engage in risky sex continue to disproportionately fuel new HIV infections in the U.S., federal health officials warned on the eve of World AIDS Day commemorations.

It’s an annual tradition from the Atlanta-based Centers for Disease Control & Prevention leading into the Dec. 1 observation: Dissecting the grim reality of HIV that still faces gay and bisexual men more than three decades after the disease was discovered. During a teleconference Tuesday, the CDC delivered fresh statistics showing that young people between the ages of 13 and 24 account for 26 percent of new HIV infections in part because 60 percent of them don’t know they are infected.

“Young gay and bisexual men report much higher levels of risky behavior than their heterosexual peers,” CDC Director Thomas Frieden says. “Gay and bisexual males are much more likely to have multiple sex partners, inject drugs, use alcohol and drugs before sex and more likely to not use condoms.”

The CDC analysis includes data from 2010 and is the latest information on HIV infections, testing and risk behaviors among young people.

Each month, some 1,000 young people are infected with HIV and, in 2010, 72 percent of those new infections occurred in young gay and bisexual men. For young black gay men, the numbers are more stark: They account for 39 percent of all new infections among the 13 to 24 age group.

Kevin Fenton (photo), the gay director of the CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD & TB Prevention, says a 12-state study that included nine urban school districts shows that young gay and bisexual men are more likely than their straight peers to have four or more sex partners, inject illegal drugs, use alcohol and drugs before sex and less likely to use a condom.

“Driving down HIV infection rates among young people is so important,” says Fenton, who recently announced that he’s quitting his CDC post and returning to England.

Fenton says that discrimination and homophobia serve as barriers to prevention and healthcare for young gay men.

“Too few young people have been tested for HIV,” he adds.

The CDC report shows that just 35 percent of 18-24 year olds have been tested for HIV, while only 13 percent of high school students have been tested. Young gay and bisexual men are also less likely to report having been taught about HIV or AIDS in school, Fenton says.

Frieden calls the data on risky sex behaviors and lower rates of condom use “shocking.” But he adds that getting people tested and linked to care, as well as reducing the viral load of HIV-positive people “will help in a major way.” He also urged a simpler approach for stemming the nation’s HIV infection rate.

“Condoms work,” Frieden says. “Ultimately you want to prevent people from being infected. There is no easy solution.”