Feluda – FnCas9 Editor Linked Uniform Detection Assay, named after a famous Indian fictional detective, is a fast and easy paper-based COVID-19 test strip expected to hit the market soon. Chemical Biologist Souvik Maiti and Molecular Biologist Debojyoti Chakraborty thought of ‘repurposing’ the existing paper-based test they had been using for sickle cell anemia and further modified it for testing coronavirus.
While the sample collection method of the paper test will remain similar to a PCR test, the speed of its result would be very similar to that of a pregnancy test. The test uses a gene-editing technology called CRISPR – Clustered Regularly Interspaced Short Palindromic Repeats, which helps detect genes specific to the coronavirus. During the trials, it has been tested on 2,000 patients, some of whom had already tested positive.
Testing remains a limited resource and something that we need to do everything we can to improve its availability. So Feluda is an important step in that direction. – said Dr. Stephen Kissler, Research Fellow, Harvard Medical School
The testing of the samples took place at the Delhi-based Council of Scientific and Industrial Research’s Institute of Genomics and Integrative Biology alongside a few other private labs. Two significant proportions were considered in the testing. Firstly, they looked at high sensitivity, ensuring that almost anyone who had the virus would be detected. Secondly, they looked at high specificity, which would effectively rule out nearly everyone without the virus. Their testing revealed 96% sensitivity and 98% specificity, which made it quite accurate.
We are trying for a simple, affordable, and truly point-of-care test so widespread testing is not limited by machines and manpower. – said Dr. Debojyoti Chakraborty, Molecular Scientist, CSIR-IGBMR and Lead Member of the team that developed Feluda
The CRISPR-based testing is considered a part of the “third wave of tests” after the time consuming and labor-intensive PCR and antigen tests. Feluda has managed to achieve the aim of providing an inexpensive and time-friendly testing kit with results obtained in under an hour and the test itself is priced at an estimated cost of only Rs. 500.
In May, the leading Indian Conglomerate, Tata Group, was chosen to manufacture the testing kits, making it the world’s first paper-based COVID-19 test available in the market. With its competitive pricing and fast results, Feluda is likely to replace antigen tests completely.
With the numerous labs and companies leaving no stone unturned to find an easier testing method to slow down the pandemic, India’s paper-based COVID-19 test paves a path to success.