The FDA have approved Roche's biologics license application for the company’s test for direct detection of West Nile Virus in donated human blood and plasma.

The cobas TaqScreen West Nile Virus Test, enables detection of the virus earlier in the infection cycle in donors who may show no symptoms of disease. According to the CDC, blood screening centers across the United States identified 340 donors whose blood tested positive for West Nile Virus in 2006 and 23 to date in 2007.

The test is designed to run on the cobas s 201 system, Roche’s flexible, modular instrument platform which automates each step of the real-time PCR blood screening process.

The test uses Roche’s highly sensitive PCR technology, the world’s leading nucleic acid amplification technology, to detect the genetic material of the West Nile virus directly in blood. The United States Centers for Disease Control (CDC) has stated that screening donated blood for West Nile Virus by nucleic acid amplification tests has markedly reduced the risk of transfusion transmission.