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.

Explore further: Researchers develop quick, cheap HIV/AIDS test

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

Researchers develop quick, cheap HIV/AIDS test

March 27, 2007

A Cornell researcher is working to develop a quick, simple and cheap immune-system test for people in the developing world. It could help HIV/AIDS sufferers in the poorest countries get appropriate treatment to extend their ...

Rapid oral HIV test shows great promise

April 11, 2007

A convenient, easy to use, and rapid alternative to blood-based HIV testing may become the new standard for field testing according to a new MUHC study. The study shows that the oral fluid-based OraQuick HIV1/2 test is 100 ...

Brown researchers create first-ever HIV rapid test video

December 12, 2007

Researchers at The Warren Alpert Medical School of Brown University have created the first educational video for patients to explain rapid tests for HIV, a relatively new tool in the fight against the AIDS epidemic.

Asthma monitoring on the Web

August 22, 2008

An inexpensive web-enabled device for measuring lung function in patients with asthma and other disorders is being developed by researchers at Texas Instruments, in Bangalore, India, and co-workers. Writing in the International ...

Taiwan scientist unveils rapid, low-cost TB test kit

March 28, 2010

A Taiwan scientist on Sunday unveiled what he said is the first low-cost and efficient test kit for identifying tuberculosis bacteria, killer of more than 1.5 million people worldwide every year.

EU gives green light for while-you-wait hepatitis B test

May 18, 2010

An inexpensive new test for the detection of Hepatitis B virus has been given regulatory approval for use in the European Union. The test, developed with support from the Wellcome Trust, delivers accurate results while-you-wait, ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...


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.