Government officials estimate that more than a quarter of new HIV infections in the U.S. strike young Americans between the ages of 13 and 24 and 60 percent of them don't know they've been infected.

A new report released Tuesday by the U.S. Centers for Disease Control and Prevention estimates that around 12,200 young Americans were infected with HIV in 2010, with young gay and bisexual men and young African Americans being hit the hardest.

Researchers found that only 13 percent of high school students and 35 percent of people between the ages of 18 and 24 have been checked for HIV, despite government recommendations for routine testing.

Researchers say that the failure to test has contributed to the reason why young people are significantly less likely to get and stay in treatment programs that can help keep the virus in check, maintain their healthy status and reduce the risk of them infecting others.

"The bottom line is that every month, 1,000 young people are becoming infected with HIV," CDC director Dr. Thomas Frieden told reporters at a Tuesday news conference. "Given everything we know about HIV prevention after more than 30 years of fighting this disease, it is just unacceptable that people are becoming infected at such high rates."

"That so many young people become infected with HIV each year is a preventable tragedy," Frieden said in a statement. "All young people can protect their health, avoid contracting and transmitting the virus, and learn their HIV status."

CDC officials estimate that every year around 50,000 people are infected with HIV in the United States and young people make up around 7 percent of the 1.1 million Americans infected with HIV.

While African Americans make up just 12.6 percent of the overall population, they represent nearly 60 percent of new infections that occur among American youth. Researchers found that 20 percent of youth infections occur in Hispanics and 20 percent among white youth.

The report also found that young men were significantly more likely to be affected, representing 83 percent of youths infected with HIV.

Researchers explain that this was mainly because of significantly higher rates among gay and bisexual males who were found to be less likely to use condoms and more likely to have multiple partners and drink or do drugs before having sex.