A decline in HIV diagnoses in the U.S. was released in a report Saturday, citing a decrease of about one-third between 2002 and 2011.

The decrease in human immunodeficiency virus (HIV, which causes AIDS) was seen across the board, with the exception of certain groups of gay and bisexual men, said Center for Disease Control and Prevention researchers in a report, according to NBC.

"Among men who have sex with men, unprotected risk behaviors in the presence of high prevalence and unsuppressed viral load may continue to drive HIV transmission," the report said, according to Reuters. The group of gay and bisexual men affected are aged 13 to 24 and older than 45.

The CDC reports that more than 1.1 million people are infected, but 16 percent of those people don't know because they have not been tested.

"The annual diagnosis rate decreased by 33.2 percent, from 24.1 per 100,000 population in 2002 to 16.1 in 2011," according to the article in a special issue of the Journal of the American Medical Association.

NBC reports the special issue was released Saturday to coincide with an international AIDS (acquired immunodeficiency syndrome) meeting in Melbourne, Australia Sunday.

The news comes just days after the tragic loss of AIDS researchers aboard the Malaysian Airlines flight MH17, which was struck down by a missile while traveling in airspace over Ukraine, who were headed to this very event.

Elsewhere in the world, the story for HIV and AIDS diagnosis is different.

There has been recent criticism in India of World Health Organization service guidelines for the group that continues to see a steady rate of diagnoses, gay and bisexual men, according to The Hindu.

The WHO said in a news release July 11 that men who have sex with men should consider taking anti-retroviral medicines in addition to using condoms.

But in a country with more than 7.7 million individuals at risk, a majority of which are women and children -- unlike other countries where the majority are gay and bisexual men, the WHO guidelines are ignoring those more in need of intervention.

Overall, however, there has been an increase in treatment and prevention in recent years, which contributed to the decrease in numbers in the U.S., according to NBC.