Diagnosing HIV and other sexually transmitted infections could take as little as 15 minutes with the push of a button on a smartphone, thanks to a new device developed by researchers at Columbia University in New York.
The portable device, known as a dongle, detects HIV and syphilis antibodies and, when linked to a smartphone app, provides a digital positive or negative result that is just as accurate as most laboratory blood tests, according to a study published in February by the American Association for the Advancement of Science in the journal Science Translational Medicine.
Researchers came to this conclusion after testing the dongle on volunteer patients at three healthcare centres in Kigali, Rwanda. Lab technicians were trained to test patients using four tests – one lab test for screening HIV, a lab test and a rapid test for screening syphilis, and a test for both HIV and syphilis using the dongle and an iPod touch. They found that all the tests had similar degrees of specificity and sensitivity in detecting their respective targets, but the dongle proved to be more efficient in producing results for both diseases at once.
All you need
There are three main components required for testing using the dongle: a disposable cassette that contains chemicals that react with a blood sample and label the molecules linked with HIV and syphilis, the dongle itself, which measures the amount of HIV and syphilis markers that are present following the reaction, and a smartphone device that projects the results to the user.
Two of the traditional tests used, one screening for HIV and the other for syphilis, were in-lab procedures, meaning they required more time and money to complete. The second syphilis test was a Rapid Plasma Reagin test. Rapid test refers to any diagnostic test that is quick and easy to perform and provides fast results with little or no equipment. Most government clinics that offer HIV testing in South Africa use rapid tests.
Although rapid tests exist for HIV and syphilis, for most sexually transmitted infections testing must be done in a lab, said Francois Venter, deputy executive director of the Wits Reproductive Health and HIV Institute (WRHI). Venter did not want to comment on how appropriate the dongle would be for the country’s health system, but noted that healthcare providers were always on the lookout for accurate tests that can they can act on immediately. “If anything, it’s interesting,” he said. “This sounds like an innovative idea that would improve more rapid action in treating patients.”
Cheap and efficient
Rapid tests are the cheapest to produce, especially compared with in-lab procedures. A single dongle costs $34 to manufacture in China, whereas lab equipment used to perform the same task can run upwards of $18 000, according to the study.
Technology combining smartphone tools with diagnostic medicine is becoming increasingly accessible to South Africans, as more and more of the population is switching to smartphones. “Last year, we saw the biggest uptake ever of smartphones in South Africa,” said Arthur Goldstuck, the head of World Wide Worx, a research company that specialises in internet and mobile technology. “In the next five years we can expect to see probably 80% of cellphone users using smartphones.”
Jesse Coleman, the manager of the mobile health branch of the WRHI, said if the device proves to be as reliable as a rapid test, and is reusable and compatible with the various smartphone systems in South Africa, it has the potential to change the way HIV is diagnosed. “This would result in savings of both time and money, which are essential for any new technology to be introduced at scale,” he said.
Joan Koka is a master’s science journalism student at the University of Missouri. She’s doing an internship at the Mail & Guardian