BENGALURU: Karnataka’s Technical Advisory Committee has recommended that the state government procure Omisure testing kits for COVID-19 diagnosis. The kit is a version of RT-PCR that detects all variants of SARS Covi-2 virus like Alpha, Beta, Gamma, Delta and also Omicron. Members of the committee believe the kit will make whole genome sequencing more focused and reduce the load on WGS labs.
“The sensitivity is 100% and specificity 99.25% for Omicron and nearly 100% for all other variants. The kit is approved by the ICMR and will shortly be available in the market,” said a report submitted to the government.
The committee said the kit has both S gene dropout and S gene specific mutation amplification for the first time in the world. Hence, it is an Omicron “stealth variant” spotter and detects all sub-lineages of Omicron such as BA.1, BA.2, and BA.3. This is a clear advantage over existing S gene dropout kits which are known to miss these sub-lineages. This is because the Omisure kit uses an entirely different region other than 69-70 amino acid deletion which is the basis of other kits.
The turnaround time per test is also less compared to other test kits. It is about 2.5 hours from sample collection to result generation. The kit is priced at Rs 250 and if Karnataka is procuring about five lakh tests, the TAC members said the cost would come to around Rs 200 plus taxes per test.
TAC members said sequencing may not be required for Omicron positive samples in the kit as it has shown 100% concordance to genomic sequencing in evaluation by the ICMR.
A senior doctor who is part of the committee said, “In fact, samples that test negative for Omicron with Omisure kit but test positive for COVID-19 should be prioritised for sequencing as they may indicate other variants, new sub-lineages of Omicron or emergence of a new variant.”