BEIJING, Nov. 30 (Xinhua) -- The share of young people around the age of twenty in all HIV infections in China almost doubled from 2008 to 2012, with male-to-male sex as the prominent contributing factor, a senior health official has said.

"Among all HIV cases reported across the country last year, 1.7 percent were Chinese youths aged between 15 and 24, up from the 0.9 percent in 2008, and the number of infected college students keeps rising," said Shang Hong, director of the HIV/AIDS key lab under the National Health and Family Planning Commission.

Revealing the figures at a promotional activity on Saturday for the World AIDS Day, which falls on Dec. 1, Shang added that 95 percent of the infected in the group were boys, and 70 percent of these infections were through male-to-male sex.

Arie Hoekman, the United Nations Population Fund's representative in China, said previously about 40 percent of new HIV/AIDS infections every day around the world are people aged between 15 and 24.

In an earlier report, Chinese President Xi Jinping stressed legal and scientific prevention and control of HIV/AIDS, calling on the public to jointly eliminate discrimination and help provide timely and effective treatment and support for HIV carriers and AIDS patients.