Oct 1, 2008 (CIDRAP News) – The US Food and Drug Administration (FDA) yesterday approved a new diagnostic test developed by the Centers for Disease Control and Prevention (CDC) that can quickly distinguish seasonal influenza strains from an evolving virus that might have pandemic potential in hours rather than days.
The test, called the Human Influenza Virus Real-Time RT-PCR Detection and Characterization Panel (rRT-PCR Flu Panel), can detect flu viruses and differentiate between seasonal and novel influenza strains, according to a statement released yesterday by the US Department of Health and Human Services (HHS).
The device isolates and amplifies viral genetic material from patients' nose and throat samples. Then it labels the viral genetic material with fluorescent molecules.
The FDA also cleared a diagnostic instrument called the Applied Biosystems 7500 Fast Dx that detects and analyzes the fluorescent-labeled viral genetic material, the HHS statement said.
The test panel and diagnostic system can detect and characterize commonly circulating human influenza viruses, avian influenza A viruses such as H5N1, and novel viruses within 4 hours rather than the days it takes for conventional tests. Also, the system can test multiple samples simultaneously.
Mike Leavitt, HHS Secretary, said in the statement that the new diagnostic test represents a significant achievement for public health surveillance. "The test allows us to better support laboratories on the front line of influenza testing in the United States and abroad," he said.
Julie Gerberding, MD, MPH, the CDC's director, said in the statement that the test provides another tool to fight seasonal influenza. "We'll now be able to detect influenza in the community faster, which allows us to take steps more quickly to protect and save lives," she said.
Three groups collaborated on the development of the new test: the CDC, Applied Biosystems, based in Foster City, Calif., and the Association of Public Health Laboratories (APHL). State public health laboratories in Virginia, Iowa, California, Massachusetts, Wisconsin, and Washington conducted clinical evaluations of the new flu panel.
CDC-qualified labs will be able to use the new diagnostic test this fall, and some facilities will be able to receive free reagents, the HHS said, adding that the test should ensure the accuracy of influenza testing results among the different sites that perform subtype testing.
Rosemary Humes, the APHL's senior advisor for scientific affairs, told CIDRAP News that labs have been using polymerase chain reaction (PCR) testing to analyze influenza viruses for a while, but they've never had standardized reagents until now. "The speed and accuracy is a great asset," she said, adding that the APHL helped develop the test and conducted validity testing.
If a lab detects a novel strain with the new diagnostic testing system, the results will be more credible, Humes said.
Leavitt said the test's ability to identify emerging influenza viruses is especially important. "This breakthrough allows for a more timely detection of a pandemic virus, which helps in determining when to begin broad control strategies as well as life-saving mitigation measures, such as closing schools, cancelling social gatherings, and informing businesses to begin work-at-home policies," he said in the statement.
Sep 30 HHS press release