Despite last week removing a ban on visitors with leprosy entering the country -- a move state media highlighted ahead of next month's Games -- the long-time block on people with HIV or AIDS remains in place.
The ban would mean that basketball legend Earvin "Magic" Johnson -- who won an Olympic gold with the US "Dream Team" in Barcelona in 1992 a year after announcing he had contracted HIV -- would not be allowed entry to Beijing as a tourist.
Connie Osborne, a senior World Health Organisation's advisor on HIV-AIDS in China, said she had hoped that China would review the "sensitive issue" ahead of the Games.
She added that reducing the stigma of HIV sufferers was one of the most crucial steps in China addressing its patchy record on the disease.
"That is still an ongoing battle. We have won a few battles, but we have also lost a few," Osborne, a Zambian doctor, told AFP.
"When we do not address stigma and discrimination, people who may be affected and those at high risk tend to go underground," she added.
Despite the difficulties, Osborne said China had made real progress in other areas, in particular increasing awareness at a local level and improving the quality of treatment in the worst hit provinces, such as Henan and Yunnan.
"We have seen increased commitment by local government. When I first came it was just central government," said Osborne, who has been here from more than three years.
Organisers of the International AIDS Conference, which is set to meet in Mexico City from August 3 to 8, have condemned countries which refuse to lift travel restrictions.
"International AIDS Society (IAS) member experts in infectious disease and public health have long held that laws and policies barring the entry, stay or residence of HIV-positive people do not protect the public health and may in fact impede effective responses to HIV," the organisation said in a recent statement.
More than 20,000 professionals from around the world will gather to discuss the global response to HIV-AIDS at the conference.
Currently, some 67 countries have some sort of HIV-specific laws that restrict the entry of people living with HIV, although the United States has recently made significant moves towards lifting its ban.
China requires short-term entrants to declare their HIV status at the border, while long-term stays require compulsory tests, according to the Global Database of HIV-related travel restrictions.
Neither China's ministry of health nor the foreign ministry answered AFP questions about the ban, and visa application forms on the foreign ministry website still included the HIV question.
Zhu Jing, a spokeswoman for the Beijing organisers, said athletes and delegates would not have to give their HIV-AIDS status.
"For the Olympic family members, if he or she is an AIDS patient, he or she can still come to Beijing," she told AFP.
The latest study by China's ministry of health, along with the WHO and the United Nations, found that 700,000 people were HIV positive in China at the end of 2007, although campaigners have warned the figure could be up to 10 times higher.
Thousands were infected during the 1990s through tainted blood transfusions at illegal blood collection stations, but the focus of attention is now shifting to high risk groups such as gay men and sex workers.
China has made moves to improve its understanding of the gay community -- homosexuality was still considered a mental illness until 2001 -- one of the areas where it is approaching international norms, Osborne said.
There has also been a new emphasis on addressing the rising number of heterosexual infections, often among migrant workers in large cities.
However, progress is undermined by China's aggressive stance on any help from groups outside the ruling communist structure, in particular non-governmental organisations.
Activist Hu Jia, who has been one of the government's most vocal critics over the AIDS issue, was this year sentenced to three and a half years in prison on charges of inciting subversion of the state, while other lawyers and campaigners have faced harassment.