Delhiites are rejoicing as the city’s COVID-19 curve is flattening. However, a lot of questions are being raised on the accuracy of the test conducted to detect coronavirus. Experts suggest that the test currently in use is not the most accurate for COVID-19 testing.
The Most Accurate Test For COVID-19 Testing Currently Available
RT-PCR (real-time polymerase chain reaction) is currently the most reliable test that is available in the market. The test involves taking a nasal or throat sample on a swab first. Since coronavirus is an RNA virus, it is first converted into DNA using a reverse transcription process.
Now, the sample obtained might have a minute viral load, which at times is undetectable. Hence, this test involves the amplification of the virus first using the PCR machine (Polymerase Chain Reaction). The PCR machine uses cycles of heating and cooling for this purpose.
The fluorescent dye is employed for the final detection. In case the person is coronavirus positive, the dye glows, else it doesn’t. The entire process is carried out by a machine.
It is reliable for it can detect even trace amounts of coronavirus. Its major drawback is the high cost (around 2500 bucks) and low speed (it takes 3-4 hours to conduct 1 test).
Test Currently In Use For COVID-19 Testing
India has paced its daily testing, and the figure stands at around two lacs presently. We could achieve this figure thanks to RAT. But the High Court has raised concerns over its accuracy as it often shows negative results even when the person is COVID positive.
The accuracy is so questionable that 65% of the people who were first tested negative in RAT later came out to be positive in RT-PCR testing in Mumbai. Error percentage of 7% is reported by Telangana Health officials.
Between 18th and 21st July, 15% of the test results came out to be falsely negative in Delhi alone. RAT is more affordable (450 bucks) and yields faster results (15-30 minutes), even though many of them are inaccurate.
Identifying The Problem
Even after ICMR’s guideline to conduct compulsorily RT-PCR on suspected individuals who test negative in RAT, many states are allegedly not carrying out enough RT-PCRs.
The capital alone is capable enough to conduct 11,000 RT-PCR tests per day. The High Court has raised concern that around 50% of it is going unutilized. In Maharashtra, hardly 1% of the negatively tested people underwent an RT-PCR for confirmation.
It raises questions on whether the fall in reported positive cases in the capital is only a facade to hide the government’s inefficiency in controlling the cases.
Image Credits: Google Images, Twitter
This post is tagged under: rapid antigen test, which is the best test for covid, how costly is rtpcr, accuracy of covid test, which is the most accurate test for covid, coronavirus is rna, rapid antigen test, how is rtpcr done, polymer chain reaction