Studies find rapid Swine Flu tests, bone cements ineffective

August 6, 2009 by Anonymous

Rapid tests for the Swine Flu, performed in a doctor's office, fail to detect the H1N1 influenza virus more than half the time according to a small study, the New York Times reported.

And the bone cement commonly used to repair fractured vertebrae is no more effective than a placebo, according to a pair of other small studies reported in the Wall Street Journal (subscription).

Swine Flu tests

The rapid tests for Swine Flu "are missing a ton of flu," Christine Ginocchio told the Times. She's director of the division of microbiology, virology and molecular diagnostics at the North Shore-Long Island Jewish Health System in Lake Success, N.Y.:

"In a study published recently in The Journal of Clinical Virology, Dr. Ginocchio found that one rapid test detected only 10 percent of the swine flu infections that could be picked up by a more sophisticated laboratory culture. A different rapid test detected 40 percent. (Dr. Ginocchio is a consultant to Luminex, a company that makes a more accurate but slower test.)"

That's bad news for companies like Inverness Medical Innovations, 3M, Thermo Fisher Scientific, Meridian Bioscience, Becton, Dickinson and Quidel, all of which make the rapid diagnostics.

The rapid tests use antibodies to detect a protein from the virus. But they only indicate the presence of influenza (in some cases distinguishing between the type A and type B strains) and don't detect the specific A/H1N1 Swine Flu strain. And if the patient's sample doesn't contain enough of the protein, the tests can return a false negative result.

And that, in turn, means using a more sophisticated test to make sure. And even a positive result can mean more tests to determine whether it's Swine Flu or another strain.

More accurate tests using the polymerase chain reaction require a lab and at least 48 hours to produce a result. A lab test made by Quest Diagnostics recently won emergency approval from the Food & Drug Administration.

Bone cement in vertebroplasty

Permalink