Dynamic HIV testing

May 19, 2010

A relatively simple electronic gadget could speed up HIV/AIDS diagnostics and improve accuracy particularly in parts of the world with very limited access to healthcare workers. The device is described in the International Journal of Biomedical Engineering and Technology.

Ali El Kateeb of the Electrical and Computer Engineering Department, at the University of Michigan, in Dearborn, explains that rapid blood tests for diagnosing have become widely available but are prone to human error in reading the results. The currently available kits require a drop of blood placed in a well containing reactant test chemicals. A positive test produces a colored band perpendicular to a "control" bar that appears only if the test procedure was carried out correctly. El Kateeb points out that even such an apparently simple test must be carried out by a trained technician and in a clinic or laboratory.

Unfortunately, errors in reading the test pattern can occur and are particularly common in parts of the world where there is a dearth of qualified technicians. The result is that false positives that have a negative psychological effect on patients are common while false negatives mean patients thinking they are free of the virus will continue to infect others unwittingly.

Previously, El Kateeb had developed a static imaging device -, akin to a simple digital camera, that could be used to identify valid and positive test results using a built-in computer chip modified to run a dedicated pattern recognition program. The static approach was not entirely successful because it relies on precise manufacture of the test kit as well as accurate placement of the "eye" of the imaging device above the test kit. Now, El Kateeb has developed a "dynamic" version of the device that overcomes this significant drawback.

In the dynamic approach, the built-in software embedded on a Reconfigurable System-On-Chip, first determines the relative position of the detector's 384 × 288 pixel eye relative to the well, illuminated by four LEDs, using a rapid analysis of pixel density in the captured image. The software then identifies the control bar and detects whether or not the perpendicular test bar is present regardless of their exact positioning within the well.

El Kateeb says this dynamic detection technique is 100% accurate in laboratory testing. The device is inexpensive, portable and self-contained and so could be made available to small clinics and pharmacies at low cost. Moreover, it requires no technician intervention, which will make it useful for rural areas in the developing world.

More information: "An accurate dynamic testing approach for analyzing images produced by quick HIV kits" in Int. J. Biomed. Eng. Technol., 2010, 4, 151-160

Related Stories

Recommended for you

Inflammation trains the skin to heal faster

October 18, 2017
Scars may fade, but the skin remembers. New research from The Rockefeller University reveals that wounds or other harmful, inflammation-provoking experiences impart long-lasting memories to stem cells residing in the skin, ...

Large variety of microbial communities found to live along female reproductive tract

October 18, 2017
(Medical Xpress)—A large team of researchers from China (and one each from Norway and Denmark) has found that the female reproductive tract is host to a far richer microbial community than has been thought. In their paper ...

Study of what makes cells resistant to radiation could improve cancer treatments

October 18, 2017
A Johns Hopkins University biologist is part of a research team that has demonstrated a way to size up a cell's resistance to radiation, a step that could eventually help improve cancer treatments.

New approach helps rodents with spinal cord injury breathe on their own

October 17, 2017
One of the most severe consequences of spinal cord injury in the neck is losing the ability to control the diaphragm and breathe on one's own. Now, investigators show for the first time in laboratory models that two different ...

Pair of discoveries illuminate new paths to flu and anthrax treatments

October 17, 2017
Two recent studies led by biologists at the University of California San Diego have set the research groundwork for new avenues to treat influenza and anthrax poisoning.

New method to measure how drugs interact

October 17, 2017
Cancer, HIV and tuberculosis are among the many serious diseases that are frequently treated with combinations of three or more drugs, over months or even years. Developing the most effective therapies for such diseases requires ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.