Testing of the infection caused by the mutated new variant of Coronavirus, Omicron, is keeping health authorities and diagnostics players on the edge.
There remains some uncertainty on the effectiveness of the Rapid Antigen Tests (RAT) and home-testing /self-test kits against Omicron. The World Health Organization (WHO), while confirming the effectiveness of the Gold Standard PCR (polymerase chain reaction) tests in detecting the infections caused by Omicron, clarified that “studies are ongoing to determine whether there is any impact on other types of tests, including rapid antigen detection tests”.
Speaking to BusinessLine , Dr Arjun Dang, CEO, Dr Dangs Labs, suggests use of multi-gene kits over those kits that target the specific spike protein that has the mutations.
“What is abundantly clear is that S-gene has changed drastically from what it was originally. The kits that are being used to detect the infection should not target the S-gene, instead they should be targeting alternate gene, E-gene or N-gene,” he said, adding that it is better to use kits that are ICMR-approved and are multi-gene in approach.
In India, the Centre has so far not issued revised testing guidelines on Omicron. Authorities in various States are continuing to use RATs, assuming the kits are able to detect the infection, since “there is no advisory from the Centre to suggest otherwise”, said a government source.
Why the worry
As observed in the previous waves, States, civic authorities and institutions usually use Rapid Antigen Tests to detect Covid infection for people crossing State borders, entering the city through train, air or road travel and in gatherings. Organisations use it as an added safety protocol to contain the spread of the infection.
With no clear indication on the effectiveness of the tests, health administrators are worried on tracking and testing Omicron cases, if it surfaces in the country.
India’s diagnostic start-up, Mylab Discovery Solutions, claimed that Omicron would have no impact on detection efficacy of its RT-PCR (PathoDetect), rapid antigen (PathoCatch), and self-testing kits (CoviSelf). The start-up, with investments from Adar Poonawalla of Serum Institute, among others, said its tests were able to detect 12 major variants.
Multinational company Abbott said its rapid and PCR tests could detect the virus and the new variant. “While the Omicron variant contains mutations to the spike protein, Abbott’s rapid and PCR tests do not rely on the spike proteins to detect the virus.” Currently, Abbott makes over 100 million Covid rapid and PCR tests a month to meet global demand.