Wired brings us exciting news about a new HIV test device which is remarkably small, and which promises to diagnose the disease in minutes rather than weeks.
The device could solve one of the vexing problems of AIDS treatment in underdeveloped countries, where patients are not within easy reach of medical facilities. By providing an on-the-spot diagnosis, doctors hope to close the gap between test and treatment, and prevent known cases from slipping through the cracks.
A test that can deliver diagnosis during one doctor visit would be a major breakthrough for regions like sub-Saharan Africa, where 25 million people are living with HIV. Current tests require technicians to draw a blood sample, then ship it to a central lab where trained personnel use expensive equipment to determine the result. Locating the patients afterward can be difficult, because they often travel from remote regions to visit health clinics.
The technology is similar to "blending digital camera technology with the brains of a Palm Pilot," says Dr. Bruce Walker, director of AIDS research at Harvard Medical School. Walker is part of a team of scientists at Harvard and the University of Texas at Austin who developed the sensor system. In tests, it has detected the amount of CD4 cells in the blood in as little as 10 minutes. The CD4 count indicates the stage of HIV in a patient, and helps doctors determine the best treatment and how much of it to administer.
The new test works by dropping a patient's blood sample onto a plastic biochip, which detects elements in the blood, says John McDevitt, the University of Texas chemist who helped develop the technology. The card is then inserted into a toaster-size analyzer, which determines the CD4 cell count.
Austin biotech startup LabNow has licensed the technology and is developing it into a system that could be used to diagnose HIV quickly and cheaply. LabNow, which recently added former Sen. Bill Bradley to its board, plans to begin clinical testing in parts of the United States, China and Africa during the first quarter of 2006, says the company's CEO Rick Hawkins. If clinical testing goes well, LabNow hopes to launch the device in parts of sub-Saharan Africa by the middle of next year.
The U.S. Centers for Disease Control and Prevention intends to evaluate the LabNow CD4 prototype, says Dr. Thomas J. Spira of the CDC's global AIDS program in Atlanta. Other diagnostic instruments are on the market, but "this one has a fairly unique type of system," he says. "There is very little manipulation that needs to be done to the specimen. It's all done in a small cassette. It doesn't necessarily need trained laboratory personnel to operate it."
And HIV is likely only the beginning for McDevitt's technology. It can be reprogrammed, he says, to serve numerous application areas by simply changing the system's molecular-level code. He is developing systems for heart disease, cancer and infectious diseases, as well as bioterrorism-screening tools and environmental-monitoring aids.
"It is a lot like putting new software into a computer each time you want to work a new application area," he says. "You need not purchase a new computer; you simply use the existing infrastructure."
Thursday, January 25, 2007
Handheld HIV Test
