Simple Paper Strip Can Diagnose Ebola in 10 Minutes: Study

US researchers said Tuesday they have developed a simple paper strip test that can diagnose Ebola and other viral hemorrhagic fevers such as yellow fever and dengue fever in just 10 minutes.

“As we saw with the recent Ebola outbreak, sometimes people present with symptoms and it’s not clear what they have,” senior author Kimberly Hamad-Schifferli, a visiting scientist at the Massachusetts Institute of Technology (MIT), said in a statement. “We wanted to come up with a rapid diagnostic that could differentiate between different diseases.”

The new device relies on lateral flow technology, which is used in pregnancy tests and has recently been exploited for diagnosing strep throat and other bacterial infections.

Unlike most existing paper diagnostics, which test for only one disease, the new MIT strips are color-coded so they can be used to distinguish among several diseases.

To achieve that, the researchers used triangular nanoparticles, made of silver, that can display different colors depending on their size.

The researchers created red, orange, and green nanoparticles and linked them to antibodies that recognize Ebola, dengue fever, and yellow fever.

As a patient’s blood serum flows along the strip, any viral proteins that match the antibodies painted on the stripes will get caught, and those nanoparticles will become visible.

The results can be seen by the naked eye, and for those who are colorblind, a cellphone camera could be used to distinguish the colors, they reported in the British journal Lab on a Chip.

Currently, the standard method to diagnose Ebola is to send patient blood samples to a lab that can perform advanced techniques such as polymerase chain reaction (PCR), which can detect genetic material from the Ebola virus.

This is very accurate but takes a day or two to yield results, and some areas of Africa where Ebola and other fevers are endemic have limited access to this kind of technology.

Last week, the World Health Organization (WHO) approved the first quick test for Ebola, called ReEBOV Antigen Rapid Test Kit, which can provide results within 15 minutes.

The test developed by U.S. firm Corgenix Medical Corp., is less accurate than the standard PCR test but is easy to perform and does not require electricity. Therefore, it can be used at lower health care facilities or in mobile units for patients in remote areas, the WHO said. (PNA/Xinhua) LAM/EBP