Amid the surging COVID-19 cases across India, the falling number of daily tests and widespread dependency on rapid antigen tests (RAT) have raised fears that a large number of positive cases could be missed in the country.
An analysis showed that . It has also been found that many states are depending mainly on RAT rather than real-time reverse transcription-polymerase chain reaction (RT-PCR) test, which is considered to be more accurate in detecting the viral infection, reported The Times of India.
As per the protocol laid by the Indian Council of Medical Research (ICMR), every positive report for the novel coronavirus infection from RAT can be treated as confirmed. But, the negative reports need to be retested using RT-PCR, the report stated.
However, it is not clear how many states are following the ICMR guidelines of retesting, said the report.
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According to the report, the reason behind the heavy dependency of many states on RAT is the quick test result. This way of COVID-19 testing does not only give the results with half an hour, but also does not necessarily need a laboratory setting.
On the other hand, results through the RT-PCR takes at least eight hours, which often end up taking days due to backlogs, it said.
The report further said that some states have reduced daily COVID-19 testing even when their positivity rate have not reduced. A high positivity rate indicates the need for more testing as with this more positive cases can be detected.
In the country, Delhi and Rajasthan have recorded the highest positivity rate of roughly 13 percent, the report mentioned. Among them, the national capital has increased the daily testing for the viral infection to reach between 2,300 and 2,700 tests per million population. Out of the total testing 70 percent are RAT, it said.
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Rajasthan, which conducts the lowest tests per million population in the country at 211, has reduced the daily testing. In October, the state was conducting over 25,000 to 28,000 tests per day, when its positivity rate was 5.5 percent to 6.5 percent. Now, the state is doing 16,500 tests per day though the number of cases is going up, the report said.
According to the ICMR, a cumulative total of 12,95,91,786 samples have been tested for COVID-19 so far with 10,83,397 samples being tested on November 19.Follow our full coverage on COVID-19
Follow our full coverage on COVID-19