Biomedical engineers at Columbia University, led by Dr. Samuel K. Sia, have developed an innovative accessory that can be attached to smartphones for rapid HIV and syphilis testing. This device, called a dongle, can detect and diagnose these two sexually-transmitted diseases in only 15 minutes.
The dongle attaches and works on any smartphone that has both a headphone jack and the ability to download and run apps; it is also compatible with iPods, iPads, and some laptops. It can fit in the palm of a hand, and is also extremely cost-efficient.
Fast, Easy, and Inexpensive
While standard materials, technology and equipment used to test for HIV cost close to $20,000, the dongle costs a mere $34 to produce. Each test costs roughly $8.50 to run. If the project is able to expand, the single-use containers needed to collect and analyze blood samples can be mass produced, which would cut the cost of tests down to less than $1.50 each.
The tests are extremely simple to conduct. The patient starts the process by having their finger pricked for a blood sample, which is then placed inside a small container that goes into the dongle. Then, a pumping system accesses the blood and it is processed. The containers that the blood go in can only be used once, so a new one is needed with every patient. Once the patient’s blood is filtered into the device, it interacts and reacts with chemicals that can indicate HIV and syphilis. This is an enzyme-linked immunosorbent assay (ELISA test), which is one of the most trusted ways of detecting and diagnosing HIV.
In 15 minutes or less, the results appear within the app on the smartphone for patients and doctors to see. The blood samples don’t need to be sent off for analysis, so it all happens on the spot. Patients immediately know their diagnosis, and health care workers can speak with them about the results.
The app used in conjunction with the dongle is important. It tracks each patient with a unique ID number, along with all of their relevant medical information.
To combat issues of battery power, some slight alterations were made to the dongle device after initial tests. First, rather than using an electric-powered pump (to move the blood samples from the container to be processed), a vacuum-powered pump was installed. It’s essentially hand-powered, which uses much less energy.
Using the headphone jack to plug in the dongle was also deemed energy-efficient because it is an outlet that utilizes little battery-power, and is standardized on most models of smartphones; it is also more energy-efficient than alternative ways of attaching the device.
However, the number of tests that can be performed before the smartphone needs to be recharged can still be low, and depends on the model being used.
So far, the dongle has been used in a pilot project to test patients in Rwanda. Both health care workers and patients deem the device a success because of it is simple, fast and efficient. Health care workers in Rwanda only required 3o minutes of training before using the dongle. This shows that the device, while performing complicated tests, is very simple to use.
In most cases, patients across the Global South have to undergo multiple expensive tests (if and when they can access health care), but the dongle has proven to be an positive alternative. These tests can be done where patients live, and cost very little. This invention has the ability to transform the way that HIV and other STI-tests are performed, which will be extremely beneficial to the populations that suffer from these diseases.
The initial research for this project was funded by the Saving Lives at Birth transition grant and the Wallace H. Coulter Foundation. A larger trial is being planned, and hopefully the device can be used by health care workers throughout many Global South countries.