'New cell phone-based tool to detect HIV'

Scientists have designed a portable and low-cost diagnostic tool, utilising a cell phone and nanotechnology, which can detect HIV and monitor its management in resource-limited regions.

Management of human immunodeficiency virus 1 (HIV), a disorder that cripples the immune system by attacking healthy cells, remains a major global health challenge in developing countries that lack infrastructure and trained medical professionals.

"Early detection of HIV is critical to prevent disease progression and transmission, and it requires long-term monitoring, which can be a burden for families that have to travel to reach a clinic or hospital," said Hadi Shafiee from Brigham and Women's Hospital in the US.

"This rapid and low-cost cell phone system represents a new method for detecting acute infection, which would reduce the risk of virus transmission and could also be used to detect early treatment failure," Shafiee said.

Traditional virus monitoring methods for HIV are expensive, requiring the use of polymerase chain reaction (PCR), according to the study published in the journal Nature Communications.

Shafiee and his colleagues designed an affordable, simple tool that makes HIV testing and monitoring possible for individuals in developing countries with less access to medical care.

Utilising nanotechnology, a microchip, a cellphone and a 3D-printed phone attachment, the researchers created a platform that can detect the RNA nucleic acids of the virus from a single drop of blood.

The device detects the amplified HIV nucleic acids through on-phone monitoring of the motion of DNA-engineered beads without using bulky or expensive equipment.

The detection precision was evaluated for specificity and sensitivity.

Researchers found that the platform allowed the detection of HIV with 99.1 per cent specificity and 94.6 per cent sensitivity at a clinically relevant threshold value of 1,000 virus particles/millilitres, with results within one hour.

The total material cost of the microchip, phone attachment and reagents was less than USD 5 per test, researchers said.

"Health workers in developing countries could easily use these devices when they travel to perform HIV testing and monitoring. Because the test is so quick, critical decisions about the next medical step could be made right there," said Shafiee.

"This would eliminate the burden of trips to the medical clinic and provide individuals with a more efficient means for managing their HIV," Shafiee said.

"We could use this same technology as a rapid and low-cost diagnostic tool for other viruses and bacteria as well," said Mohamed Shehata Draz from Brigham and Women's Hospital.

"This platform could help a lot of people worldwide," Draz said.