Human tests for SARS vaccine

China began its first human trials of a SARS vaccine with tests on four volunteers in Beijing's China-Japan Friendship hospital. The trials follow successful testing of the vaccine on animals. Some 30 volunteers are expected to take part in the first round of human testing, designed to establish that the dead SARS virus contained in the vaccine poses no risk to humans. Analysts said it would take one to two years for a vaccine to reach the market.