Avian flu-detecting chips licensed for distribution

By Colleen Taylor -- Electronic News, 1/5/2007

The best weapon against potential pandemics like avian flu could indeed prove to be a computer chip. A microarray-based influenza detection technology, dubbed "MChip," has been developed by scientists at the University of Colorado in close collaboration with the U.S. Centers for Disease Control and Prevention (CDC), and could soon be standard at medical clinics worldwide.

Holding the worldwide license to make and distribute the MChip is Quidel Corp., a San Diego-based provider of rapid point-of-care (POC) diagnostic tests. Quidel said its intent is to develop and market molecular-based diagnostic tests featuring the MChip for use in pandemic surveillance, as a tool for the clinical laboratory and at the point-of-care in the physician office laboratory.

According to Quidel, the MChip offers several advantages over current molecular-based arrays for the detection of influenza viruses, including the recently disclosed FluChip developed by the same research team at the University of Colorado at Boulder and the CDC. While the majority of molecular-based arrays use sequences from three influenza genes -- hemagglutinin (HA), neuraminidase (NA) and matrix (M)-- the MChip exclusively exploits sequences from the matrix genes. Unlike HA and NA, which mutate constantly, the M gene segment is more conserved. A diagnostic test based on this relatively stable gene segment should be more robust because it will continue to provide accurate results even as the HA and NA genes mutate and will require less frequent reconfiguration, Quidel said.

In addition, Quidel said, current molecular tests provide only information about the type of virus present in a single sample. The MChip offers the advantage of simultaneously typing and subtyping the flu virus in a single procedure, avoiding the need for additional subtyping of the virus.

The MChip has been validated in collaboration with the CDC by testing H5N1 samples collected over a three-year period from people and animals around the world and to date has correctly identified 24 different H5N1 flu strains at 97 percent sensitivity and 100 percent specificity, with no reported false positives, Quidel said.

"This new technology, once manufactured and distributed, could have the potential to revolutionize the way laboratories test for influenza," Dr. Nancy Cox, director of the influenza division of the CDC, said in a statement. "The MChip could enable more scientists and physicians, possibly even those working in remote places, to more quickly test for H5N1 and to accurately identify the specific strain and its features."