The Government is ramping up testing to detect COVID-19 cases.
At present, RT-PCR or Reverse transcription-polymerase chain reaction is the most widely used method to identify the Sars-CoV-2 virus.
But since it takes five hours or more for results to come out, on Sunday, the Indian Council of Medical Research issued new testing guidelines that will give the result in 15-30 minutes.
The ICMR has sought rapid antibody testing for people with flu-like symptoms (cough, cold, low-grade fever and sore throat) in clusters and in Coronavirus hotspots across India. It also wanted all testing organisations to register themselves on its portal and upload data in real-time.
The Government is also planning to double every three days the number of samples tested through the RT-PCR process by its laboratories. It said the scope of testing will be enhanced with the newly-sanctioned rapid antibody tests for diagnosis of suspected cases.
How does a COVID-19 RT-PCR test work?
The most commonly used test currently for COVID-19 is a nasopharyngeal swab, where a special Q-tip is put up your nose or throat to take a sample.
This swab is then sent out to a laboratory that can extract the virus’s RNA. The virus that causes COVID-19, SARS-CoV-2, is an RNA virus, which means it uses Ribonucleic acid as its genetic material. It requires a process called reverse transcription or RT to transcribe its RNA into DNA. Because there’s not much material in one sample, a PCR or polymerase chain reaction is used to rapidly make billions of copies so it can be analysed. With enough DNA copies on hand, scientists then apply fluorescent colours to the sample, which glows if SARS-CoV-2 is present.
What is Rapid Antibody testing?
But the rapid testing kits are quicker to get early results. They use blood samples of suspected patients and normally take around 15-30 minutes to give the result. Under this, one has to clean their finger with an alcohol swab and use the lancet provided for finger-pricks. These serological tests (means the scientific study of serum and other body fluids), are different from the nose swabs used to diagnose active cases of Coronavirus. By analysing blood samples, researchers will be able to tell if a person developed certain antibodies in the blood, indicating that they were infected by the virus and recovered.
Why Rapid Antibody test is important?
Experts say the rapid antibody testing is important for community surveillance and investigation. According to the Health Ministry, the rapid test kits could speed up the screening process in India where just about 70 per cent of testing capacity has been utilised. Several countries including China, US have already begun conducting blood tests to determine exposure to COVID-19 without even seeing symptoms.