BEIJING - Chinese experts say an increasing number of old people and college students in the country have become infected with HIV/AIDS through unsafe sexual intercourse in recent years.

Figures revealed Wednesday by the Chinese Center for Disease Control and Prevention (CDC) show that the number of HIV positive men in their 60s and above soared from 483 in 2005 to 3,031 in 2010, accounting for 8.9 percent of the total. In 2005, the group only took up 2.2 percent.

"As a result of improved living standards and health conditions, the sexually active period of old people, especially males, has been prolonged," said Wu Zunyou, director of the CDC HIV/AIDS prevention and control center. "With considerable sex drive even after retirement and the death of spouses or their lack of interest, some elderly have resorted to sex services."

"Many tended to choose secluded and low-end venues and didn't use condoms, which made them highly vulnerable to HIV infections," Wu added.

Also, a total of 1,252 HIV/AIDS-infected students were discovered as having the virus between January and October, accounting for 21 percent of all student cases. Infection has been especially obvious in the past two years among male college students aged between 20 to 24, according to the CDC.

"The distribution of HIV/AIDS cases in our country is now wider and more scattered than ever, posing great difficulties for prevention and control efforts," Wu warned, noting that more cases were being discovered unexpectedly during hospital checks.

It is estimated that that there were 48,000 new cases in the country in 2011, of which 81.6 percent were transmitted through sexual intercourse. The proportion for the period between 1985 and 2005 is only 11.6 percent, said Wu.

Wu estimated that 63.9 percent of the country's currently living HIV carriers and AIDS patients were infected through sex, and those through heterosexual intercourse taking up 46.5 percentage points.

"A recent survey found that nearly one-fourth of respondents said they had more than one sex partner. Considering those who refused to admit that, the actual proportion might be astonishingly high," Wu said, urging more education campaigns for safe sex and loyalty in marriage.

Also on Wednesday, Minister of Health Chen Zhu noted various issues in the fight against the disease, including inadequate implementation of free treatments policies, insufficient funds for projects and inactive participation of organizations at the community level.

"Social discrimination against the HIV/AIDS-infected population is still severe and will be very hard to eliminate," Chen said.

China currently has 346,000 registered HIV carriers and AIDS patients, although the actual number is predicted to hit 780,000 by the end of 2011, according to previous reports.

Chen vowed the country will make an all-out effort in the next five years that include wider coverage of treatment, an intensified education campaign to promote public awareness, better protection of carriers and patients' rights, and the bolstering of the role of NGOs.

According to Chen Zhu, the country has set a goal to control HIV/AIDS infection cases below 1.2 million by 2015.

"This will be an extremely tough battle," Wu said.