The University of California, Santa Barbara, has developed a new, cheaper method for possible home COVID-19 testing using a smartphone camera and app.
The new testing method, which is the subject of a research paper printed in the journal JAMA Network Open, uses some essential lab equipment and the app Bacticount to detect possible pathogens in a person’s saliva. In order to use it, you load a saliva sample into a test kit placed on a hot plate. Then you add a specific reactive solution, similar to what is used for COVID tests done at home today, that amplifies the viral RNA that might be present in the spit.
Loop-mediated Isothermal Amplification, or LAMP, is the name for this specific process.
The sample would be placed inside the box on the left, where an LED would illuminate it. Credit: University Of California, Santa Barbara
After any potential viral RNA has been amplified, you place a cardboard box with an LED light over the top. Then, a smartphone’s camera can take a picture of the LED-lit box, where it will be able to see if any color changes indicate the presence of COVID-19. If a viral load is present, the solution should produce a bright red light. The red light should appear faster if the viral load is large, aka more contagious. Depending on how quickly that light appears and registers, the app will estimate your viral load.
According to Gizmodo, the cost of using this new test setup would be “less than $100, plus the cost of the smartphone you’d need to run the app.” For each subsequent test, which would presumably require a new test kit, you’d be out about $7 – a bargain compared to the hundreds that insurance companies have been charging for certain PCR and rapid tests.
Using this method, the researchers believe this test could have the same accuracy rate as a PCR test, and the ability to conduct the test at home could allow for much quicker results than a PCR in a doctor’s office that handles hundreds of samples every day. It is important to note that this study did have a relatively small sample size of 50 people, so further research will be needed before it can be implemented more widely.
Although the kit was originally designed for “resource-limited settings,” its head researcher told Gizmodo that it could be easily adapted to home use. Bacticount is currently only compatible with Samsung Galaxy S9 due to its specific camera calibrations. As research continues, this could change, and more smartphone cameras could utilize the testing technology.