Rapid antigen tests account for close to 50% of Covid-19 tests in India: Govt data

While RT-PCR is the gold standard for Covid-19 testing because of the high sensitivity of the test, RAT is preferred in areas where mass-scale testing needs to be deployed for it gives results in minutes and is cheaper

Rapid antigen testing (RAT) accounts for a majority of tests being performed in the country to detect the coronavirus disease (Covid-19), according to the government data.

Of the 120 million samples tested for Covid-19 so far, 49% have been done using RAT.

“The country has tested close to 12 crore [120 million] samples for Covid-19 so far, which is the second-highest in the world, of which 46% tests have been done using reverse transcription-polymerase chain reaction (RT-PCR), 49% through rapid antigen testing, and the remaining 5% have been performed using tuberculosis (TB) testing platforms—CB NAAT and TRUE NAAT,” said Rajesh Bhushan, secretary, Union ministry of health and family welfare.

Both CB NAAT and TRUE NAAT are essentially used to perform TB testing in the country, and the Indian Council of Medical Research (ICMR) has allowed the testing platforms to be repurposed for testing samples to detect Covid-19.

While RT-PCR is the gold standard for Covid-19 testing because of the high sensitivity of the test, RAT is preferred in areas where mass-scale testing needs to be deployed for it gives results in minutes and is cheaper. The test is highly specific, which means can accurately detect true positive cases.

However, because of the limitations of the test in terms of not being that accurate in detecting true negatives, the ministry has advised states to mandatorily test through RT-PCR all RAT negative samples of individuals having Covid-19 like symptoms. RAT is also quicker and gives results in minutes rather than hours taken to get RT-PCR test results.

The rapid antigen test is also cheaper to perform as compared to the RT-PCR, which is a complicated test requiring a specialised laboratory.

ICMR, the central body that is spearheading Covid-19 testing in the country, has approved more than 2,000 laboratories to perform Covid-19 tests across the country.