The UN AIDS chief said 50 million people are at risk from the disease in China and the government must do more to reach out to civil society and work with vulnerable groups such as homosexuals.
China has 319,877 confirmed HIV cases but 740,000 are estimated to be infected, Michel Sidibe told AFP in an interview late Tuesday, citing figures compiled by UNAIDS, the World Health Organisation and China's health ministry.
But up to 50 million others are in high-risk groups such as sex workers, migrant labourers and drug users, he added.
The UNAIDS executive director said he chose China as the place to launch the UN 2009 AIDS epidemic update on Tuesday, partly to push Chinese leaders to work with non-government groups, who often must operate unofficially in China.
"I wanted to come here to push a few agendas ... I'm pushing them for a civil society ... they don't have mechanisms to register them and monitor how they are doing," Sidibe said.
With sexual transmission between gay males accounting for 32 percent of new infections in China last year, Sidibe said more must also be done to engage the homosexual community, which struggles for acceptance in China.
Sidibe travels to Beijing on Wednesday for talks with Chinese leaders and to launch a new public awareness campaign featuring NBA star Yao Ming on Friday.
He said the involvement of such a popular and high-profile star as Yao was a positive signal that Chinese society was getting more comfortable discussing AIDS.
Health Minister Chen Zhu joined Sidibe at the UNAIDS report's release in Shanghai and acknowledged China faced "a long march" in AIDS prevention and control.
Calling AIDS "an engine for social change", Sidibe said it was forcing Beijing to openly discuss controversial issues.
"When you talk about AIDS, you talk about sex, you talk about human rights," he said.
Chen has agreed to hold an AIDS human rights forum early next year to discuss issues including patient care, women's role in society, sex workers, and the homosexual community, Sidibe said.
He said the forum would help carve out space for civil society in China's AIDS dialogue.
"Like most former Communist countries, you have a nascent civil society," he said.
"It has never been well-organised, it has been characterised by the position of individuals, vocal activists who were able to voice their position a little. I'm seeing major progress."
Sidibe said the government is adopting a more open approach due to the evolution of the epidemic in China, which has shifted from mostly intravenous drug use to sexual transmission.
Sexual transmission accounted for more than 72 percent of new cases last year.
"They have today 30 to 50 million people at risk in China because of their behaviour," Sidibe said.
He based those numbers largely on China's huge floating population of migrant workers, traditionally a high-risk group as it includes prostitutes and migrants who pay them for sex.
"Multiply that by the number of spouses, by the number of children and family members who could be affected -- it's a major risk they want to manage," he said.
"(China is) dealing with it with energy and pragmatism -- which is important to say to the rest of the world. That doesn't mean there aren't issues."
Sidibe's words of support for civil society were welcomed by Wan Yanhai, the Beijing-based founder of the AIDS Action Project and one of China's most prominent AIDS activists.
But he said China's control-conscious government was still far from openly embracing civil society groups in a manner sufficient to meet the epidemic.
"Every year we see UN people coming to China. They do many good things for the publicity, but the work they are doing is not helping civil society."
Wan said the government was starting to selectively work with non-governmental groups.
"They select NGOs who defend the government, not those that defend people's lives," Han said.