Wang Gang should be one of modern China's success stories. Confined to a wheelchair by haemophilia, he graduated from Shanghai's Jiaotong University in accountancy through a home study programme. Taking advantage of city policies to promote disabled employment, he gained a job as a college administrator. The Shanghai authorities subsidised a motorised wheelchair to take the 32-year-old to work.

Instead, he is one of the most potent symbols of the safety scandals that are undermining confidence in Chinese food and drugs. Six years ago Mr Wang (his given name has been changed to protect his identity) discovered he was HIV positive. Since last October he has been in the medical wing of a Shanghai prison for his role in a protest against the state-owned company whose blood products he and around 100 other local haemophiliacs say are responsible for their infection.