COVID-19 PILOT PROJECT: 500 undergo rapid antigen testing in Punjab, positivity rate 15.6%

Over 500 people have undergone Covid-19 rapid antigen testing in the five worst-affected districts of Punjab in the last five days as part of the state health department’s pilot project.

Of the 504 symptomatic people tested in Amritsar, Jalandhar, Ludhiana, Mohali and Patiala districts, 79 tested positive for the coronavirus, with a positivity rate of 15.6%, health officials said.

Antigen testing detects foreign substances found on or within the SARS-CoV-2 virus in the body through nasal swab samples. The test is performed outside the conventional laboratory setting and is used to obtain a diagnostic result in 30 minutes.

Also, the swab samples of those tested negative for Covid-19 in the antigen test reports were sent to the virus research and diagnostic laboratories (VRDL) of the state for confirmatory RT-PCR (real-time polymerase chain reaction) testing to check whether both the tests show same results.

The RT-PCR is the most commonly used test for Covid-19. It is based on a process that repeatedly copies and amplifies the specific genetic fragments of the virus. The test is done in a lab and it takes 5-8 hours to test a sample.

The state government started the antigen testing project on July 10, with 5,000 kits at its disposal. Nearly 1,000 testing kits were given to each of the select districts.

“So far, 252 antigen tests have been done in Jalandhar, the highest among all the districts, followed 124 in Patiala, 66 in Ludhiana, 51 in Amritsar and 11 in Mohali. Eighteen people tested negative in antigen tests were found to be infected in RT-PCR tests,” state Covid-19 nodal officer Dr Rajesh Bhaskar said.

“Also, some RT-PCR reports of people found negative in antigen testing are awaited. Since the antigen test results are available within 30 minutes, we are able to identify and isolate positive cases to prevent further transmission of the infectious disease,” Dr Bhaskar added.

‘MORE ACCURATE THAN RAPID CARD TESTING’

The health officials said the reports of antigen testing kits are showing more accurate results than those through rapid card testing, the testing technique which was discontinued by the state after contradictory reports surfaced.

“So far, all those found positive in antigen testing have also been found infected in RT-PCR tests. The only drawback of this is that we are using antigen testing only on symptomatic people,” said Amritsar assistant civil surgeon Dr Amarjit Singh.

“For cross-checking, we have also done RT-PCR tests on some people found infected in antigen testing and most of the reports were accurate,” Dr Bhaskar said.

The state government will conduct antigen testing on the migrants coming back to the state in the wake of reopening of industries and for work in paddy fields.