Omicron can be detected via RT-PCR and Rapid Antigen tests: Sources

New Delhi: Omicron, the newly emerged Covid variant that has put several countries on alert can be detected via RT-PCR and the Rapid Antigen Tests (RAT), sources from the Health Ministry said on Tuesday.

This comes amid speculation that the available diagnostic measures may not be able to accurately the highly mutated Omicron variant. Moreover, the sources have indicated that state governments have been advised to ramp up COVID-19 testing for early identification of positive cases, and early management.

Meanwhile, the World Health Organisation (WHO) has stated that countries using PCR tests containing the 'S' gene could also utilize the 'S' gene target failure as a proxy marker for infection with the Omicron variant of Covid.

"Studies are ongoing to determine whether there is any impact on other types of tests, including rapid antigen detection tests," it said.

Reverse transcription PCR or RT-PCR test, one of the most widely used methods for detecting COVID-19, is believed to be highly sensitive and accurate.

RAT, which detects the proteins on the surface of the virus called an antigen, is typically faster but is less sensitive.

'Omicron' - found in at least 13 countries so far - was declared a variant of concern last week by the WHO with the classification putting it in the same category as globally dominant Delta, and its weaker rivals Alpha, Beta, and Gamma.

In a warning, the WHO on Monday said it poses a "very high" global risk and could have "severe consequences" where there are surges.

The government on Sunday asked all states to step up intensive containment and active surveillance.

"It is imperative that intensive containment, active surveillance, increased coverage of vaccination, and Covid-appropriate behaviour be enforced in a very proactive measure to effectively manage this variant of concern," the Health Ministry said.

The government also announced a list of "at-risk" nations - the UK, South Africa, Brazil, Bangladesh, Botswana, China, Mauritius, New Zealand, Zimbabwe, Singapore, Hong Kong, and Israel.

Every passenger coming to India from the affected countries has to fill a self-declaration form and show a negative RT-PCR test report.