NEW YORK, April 22 - PCR-based tests for the SARS coronavirus are being made by various labs, but the US Centers for Disease Control said today that they are still trying to determine, along with World Health Organization labs, the accuracy of these tests.
"There is a lot of interest in getting good testing protocols available for this agent," said Julie Gerberding, the CDC director, in a press conference this afternoon. Since the CDC and a Canadian team published their sequences online last week, she acknowledged that "just about anybody with bio biotechnical capabilities" can create a PCR-based test from the sequence.
"The problem is knowing whether the test you are using is accurate or not," Gerberding said. "And the only way you can really determine that is by using that test on a wide variety of clinical specimens, including people that you are vary confident have the infection as well as people that you are very confident don't have the infection. And that takes time. But it also takes access to a whole panel of specimens."
The CDC has compared its SARS coronavirus sequence to that of the Canadian team, and has found few differences, Gerberding said. To shed light on why some people are getting sicker than others, "we need to sequence more viruses," she added. This "will be a longer term investigation."
Additionally, Gerberding said reports of a zoonotic connection to the SARS coronavirus are still at the level of "speculation,": So far no there is no evidence in sequence phylogeny for this connection.
Since the CDC and the Canadian team, at the
GenomeWeb coverage of SARS
Canadian Team Sequencing SARS Virus (Apr 9, 2003)
CDC Completes SARS Virus Genome Draft On Heels of Canadian Team (April 14, 2003)
Canadian Team Leader: SARS Coronavirus Genome Has 11 Novel ORFs (April 15, 2003)
CombiMatrix Creates Microarray Based on SARS Genome Data (April 16, 2003)
Coronavirus Linked to SARS: WHO (April 16, 2003)
Singapore Genome Institute Joins SARS Sequencing Fray (April 16, 2003)