Rapid antigen tests now account for almost half of daily controls | India News
The increased use of RAT has helped the government increase testing for early detection and clinical management of infected cases and isolation of contacts. However, ICMR is examining concerns raised about ‘false negatives’ under RAT and RT-PCR remains the definitive gold standard test.
While the number of daily Covid-19 tests almost doubled in the past month, the RAT ratio increased by 40-45% in late July compared to just 4-8% in its first week, they show. official data.
The average number of daily Covid-19 tests increased from 2.40,620 in the first week of July to 4.68,263 in the last week of July, up 94.6%. However, in the last week, there were days when more than 5 lakh tests were performed. On July 30, more than 6.43 lakh tests were performed in 24 hours, with RAT representing 45.68% of these tests.
“There is now a greater tendency to use rapid antigen tests because they are much faster and cheaper compared to RT-PCR, although that is still the definitive gold standard test for detecting Covid-19 infection.” While there was an urgent need to speed up testing across the country, the introduction of rapid antigen tests has increased the total number of tests by at least 50%, “said an official.
India is currently conducting 14,640 tests per million population to detect the infection and this shows a steady upward trend with an increasing number of daily tests. About 24 states and UTs have reported tests higher per million than the national average.
In addition to RT-PCR and RAT, India is also conducting TrueNAT and CBNAAT tests, but these represent a smaller percentage of the total compared to the former. Together, RT-PCR and RAT represent more than 90% of the total tests performed in one day.
Authorities say the increased testing is in accordance with the key strategy of “aggressively test, efficiently track and isolate and treat promptly,” followed by the government for the management of Covid-19 along with the states.
“The effective implementation of this approach has led to increased testing capacity across the country and has made Covid testing of people easier,” an official said.
However, there are continuing concerns related to false negatives under RAT and the lack of repeated testing through RT-PCR to confirm the negatives. The efficacy of the protocol depends on the states that ensure that symptomatic negatives are tested and that there is a follow-up to verify the indications among other negatives. Some experts feel that such errors are affecting the positivity rate despite a significant increase in overall tests.
The ICMR is evaluating the accuracy of rapid antigen tests using a mathematical model and will analyze whether the proportion of false negatives is substantially high.