Young gay men are the frontline of China’s battle to prevent the spread of HIV/AIDS, with new cases in the group increasing fourfold, one of the fastest rates of any segment of the population.

More than 2,300 students between 15 and 24 tested positive for HIV/AIDS in the first nine months of this year, according to data from the Chinese Centre for Disease Control and Prevention (CCDCP) that was cited by the official Xinhua News Agency late on Wednesday.

By the end of September, more than 654,000 people were living with HIV/AIDS in China, Xinhua said.

As the problem worsens, Beijing has turned its HIV/AIDS prevention efforts towards high-school and university students.

China’s first-ever health center focusing on preventing the spread of the human immunodeficiency virus, which causes Acquired Immune Deficiency Syndrome, among those aged 15-24 was opened in Beijing on Saturday, according to the official China News Service.

The proportion of cases caused by unprotected sex between males in that age group had risen to more than 80 percent from around 60 percent in 2008, Bao Yugang, China director at the AIDS Healthcare Foundation, a non-profit group told China News at the launch of the center.

World AIDS Day is celebrated on Thursday and Peng Liyuan, China’s popular First Lady and a World Heath Organization HIV/AIDS prevention goodwill ambassador, attended an event at a Beijing university on Tuesday to raise awareness among students.

The government has struggled to raise awareness about safe sex and the need for regular checks among high-risk groups, with many HIV-positive individuals going untested.

“When I was first confirmed (as HIV-positive) it wasn’t because I intentionally went to get tested, it was when I was having treatment for an illness in hospital, the hospital just did a test without telling me,” said Xiao Ji, a 25-year-old who identifies as gay man and who used a pseudonym.

“When the results came out (the hospital) refused to treat me,” he said.

The spread of HIV/AIDS remains a serious issue in China, with nearly 9,000 deaths from AIDS and more than 34,000 new cases in the first eight months of 2016, according to a CCDCP report.