On the day marking the global fight against Aids, Beijing migrant workers are given free condoms and safe-sex advice World Aids Day was marked across the mainland yesterday with activities ranging from the practical to the dramatic. A team from the Centre for Disease Control and Prevention visited a construction site in Beijing's Chaoyangmen district at noon. Using frank talk, billboards and information packs, the medical staff gave workers advice on safe sex. The construction workers clamoured for the free condoms being passed out, and 5,000 were snapped up in a few minutes. That forced the medical team to hold another 5,000 in reserve, for distribution before workers return home for the Lunar New Year. Hundreds of workers listened attentively to the hour-long talk, especially to the demonstration on how to use a condom. 'They are young when they become sexually active,' said Li Xiaohong of the centre. 'They are not only away from their home town, but probably also from their regular sexual partners.' Dr Li said awareness was the key to stopping the disease from spreading. 'But the workers usually don't have much knowledge about Aids, so we need to strengthen sex education,' she said. The campaign has already visited university campuses. On Saturday in Tsinghua University, male students took turns wearing a pregnancy simulator - a stuffed vest weighing 12kg - while trying to pick up sweets from the ground. Male and female students were given the opportunity to put condoms on six mock penises. One female freshman was quoted as saying she was not shy about doing this as she wanted to know how to protect herself. The Ministry of Health also launched the nation's first commemorative stamp featuring the symbolic red Aids ribbon. Officials said it showed the government's support for the awareness campaign. The ministry yesterday also officially released a new assessment of HIV/Aids on the mainland, jointly drawn up by Beijing and the UN. The study showed the number of people liable to contract HIV/Aids will rise sharply in coming years if no preventive action is taken. In the run-up to World Aids Day, about 20 Aids patients in Zizhong, Sichuan province, acted out a play they had written themselves, titled Live and Let Live - the theme of this year's global event. The play tells the tale of a man who falls on hard times and sells his blood to raise cash, only to become infected with HIV. It dramatises his struggle to win acceptance in society. The cast said they staged the play to fight against discrimination. The state-run broadcaster, China Central Television, has broken its own long-term ban on advertising contraceptives. In the past few days it has been carrying a 30-second condom advertisement, encouraging people to prevent the spread of Aids.