Are Antibody Tests for Covid-19 Really Helpful?
In the recent developments to tackle Covid-19, the medical fraternity has come up with a new method to detect Coronavirus. Claiming to be one of the most accurate tests for Covid-19 the success rate of this rapid antibody test in India is still not very clear. The Indian Council of Medical Research (ICMR) had earlier advised the states to use the antibody test for Covid-19 and shift their focus from real-time reverse transcription-polymerase chain reaction (RT-PCR) to rapid antibody test.
However, many states have raised concerns over the reliability of results that the Covid-19 antibody test kit delivers. The most recent example in this regards is from Rajasthan where the new rapid antibody test kits have failed to detect the presence of antibodies in a patient even though the laboratory reports confirm him to be Covid-19 positive.
What is Rapid Antibody Test?
The rapid antibody test is a new method developed to diagnose the novel Covid-19 disease. It is an indirect approach to detect the disease. Also known as serological test, this antibody test for Covid-19 uses blood samples from patients to find out the presence and quantity of antibodies in them.
What is the Difference Between Rapid Antibody Test and RT-PCR?
A lot of discussions between medicinal fraternities are taking place in order to come up with effective, timely and accurate results for Covid-19 testing. While some advocate the use of Coronavirus antibody tests as they deliver timely results, some are still in favour of using RT-PCR test. The results delivered through this method are more accurate and reliable. Some major differences between rapid antibody test for Covid-19 and RT-PCR include:
- Speed of Result: The results of tests done using Covid 19 antibody test kits are quicker as compared to the results delivered by RT-PCR tests.
- Accuracy: Though antibody tests for Covid-19 are delivered quickly, they are not as accurate as the results that are delivered using RT-PCR.
- Procedure: The antibody test uses blood samples. RT-PCR uses swab from the nose or throat as the sample.
- Protocol: If a person is tested negative using the antibody test of Covid-19 he or she might have to give their sample for RT-PCR for final confirmation. Whereas on being tested negative through RT-PCR it is assumed that the symptoms could be of normal influenza.
- Usage: The rapid testing could be of great help in hotspots and can help detect the presence of the virus in possible clusters. However, the final call will be taken only after conducting the RT-PCR test.
How is Antibody Test for Covid-19 Useful?
The rapid antibody test for Covid-19 is comparatively quicker and cheaper. The RT-PCR requires specialised laboratory and trained technicians and RNA extracting machines making it expensive and less approachable. Whereas the antibody test can be conducted anywhere and is useful for the detection of disease in masses.
Rapid Antibody Tests in India
Two Chinese companies were licensed to sell five lakh units of Covid19 test kits to India. Some of these kits were distributed to states whereas some were used directly by ICMR. However, as soon as the first batch of kits were deployed in some states, reports of inaccurate and erroneous results started floating. Now the government has collaborated with several other countries that will provide the antibody testing kits to India.