Sars blood test for sale

China says it has approved the sale of a blood test for the Sars virus.

The test can detect antigens for the virus that causes severe acute respiratory syndrome one to 10 days after exposure, says the official Xinhua News Agency.

The test "is very sensitive and safe, as well as less expensive and easy to use", Xinhua said, citing an official of the State Food and Drug Administration. It did not say who developed the test or whether it might be sold outside China.