CARRIERS of the AIDS virus are being denied entry to countries around the region, including China, Japan and Vietnam, prompting a warning that the practice is discriminatory and will not stop the spread of the killer disease. A survey of visa applications for six countries found that only Thailand and the United States allowed unrestricted access to visitors who are HIV-positive. Britain does not have a clear policy on the issue, although an immigration spokesman said entry could be refused on ''medical grounds''. But the Hongkong AIDS Foundation's education officer, Mr Mike Sinclair, who has the virus which leads to AIDS, said refusal of entry should be stopped because it was of no use in controlling the spread of the disease. Mr Sinclair has been denied a visa to travel to Vietnam next month to perform in A Midsummer Night's Dream with the Hongkong Players. He said the Hongkong Players informed the Vietnamese Government about his condition and were told ''HIV-positive people will not be allowed to enter the country''. ''It is alarming that my world has shrunk to that small,'' Mr Sinclair said. ''I know my condition and I am committed to taking precautions. Society should grant me the rights of a normal person. ''It is the first time people have mapped out where I can go and where I cannot go.'' A letter from the deputy director of the Youth Theatre of Vietnam, Mr Tren Tien Thuet, said: ''We asked our Ministry of Culture and Information about Mr Michael Sinclair, but it is not possible for him to visit. Please make arrangements for a replacementfor his role.'' Vietnam was the first place Mr Sinclair applied for a visa after he publicly admitted that he was HIV-infected late last year. He visited China last June when he knew he was infected, but wrote ''no'' on forms asking if he was an HIV carrier. The vice-president of the Democratic Alliance for the Betterment of Hongkong, Mr Tam Yiu-chung, said he understood there was legislation in China forbidding foreign HIV-carriers from entering the country. Mr Sinclair said the policy was highly negative because it discouraged people from acting responsibly by taking precautions to protect others. People might intentionally not use a condom during sex so as to avoid suspicion from their partners, he said. The policy also might mislead people into thinking AIDS was a foreign disease and could be stopped at the border, but this could hinder the development of a proper public health policy on the issue, he said. China tried in January to introduce HIV testing at the Hongkong border for frequent visitors, but stopped after about a month following protests from businessmen and health officials in the territory. Of the six countries contacted by the South China Morning Post to check the impact of AIDS on visa applications, only the American and Thai consulates said there were no restrictions on HIV carriers. Japan does not require HIV carriers to admit to their condition on visa applications, but they must make a declaration on arriving at the airport, according to the senior officer of the Japanese consulate's visa section, Mrs Junko Kato. Anyone later found to be a carrier would have to return to the point of departure, she said. As for Britain, an immigration spokesman, Mr Wong Hing-wa, said a visitor could be refused entry even after being issued with a visa. ''You can still be refused entry into the UK by the immigration officer if he has certified that refusal is justified on medical grounds,'' he said. Asked if AIDS was considered one of the ''medical grounds'', Mr Wong said the rule did not specify a particular disease and all diseases would be considered. The immigration officers can ask anyone to be medically examined on arrival in the UK. Australia also does not have a specific ban on HIV carriers, but applicants for visas are asked to state if they are carriers of contagious diseases such as AIDS, pneumonia and hepatitis. In general, the implementation of entry restrictions on HIV carriers largely depends on whether a traveller declares his health condition. Mr Sinclair said there were 13 million HIV carriers according to the World Health Organisation, and they could all face problems in travelling.