ICMR asks states to stop using rapid Covid-19 tests after complaints of patchy results

India is currently using rapid antibody tests for Covid-19 from China, South Korea, Germany and France, alongside those from domestic manufacturers.

A medical worker puts blood sample in a kit for rapid blood test | Representational Image | Carlos Becerra | Bloomberg

New Delhi: The Indian Council of Medical Research (ICMR) has asked states to stop using rapid antibody test kits for Covid-19 diagnosis for two days until they are validated again. 

The directive came after the rapid antibody tests, which reveal if a person has contracted coronavirus and developed antibodies against it, were found to yield discrepant results. On Monday, Rajasthan had approached the ICMR, India’s apex medical research body, with a complaint that just over 5 per cent of the antibody tests had proved accurate.

While the RT PCR (real time reverse transcription polymerase chain reaction) tests, the gold standard to detect Covid-19 infection, can take up to a day to yield results, rapid antibody tests take less than 30 minutes and require no laboratory. The latter are also cheaper, costing up to Rs 500 a pop against around Rs 4,500 for RT PCR.

India is currently using rapid antibody tests from China, South Korea, Germany and France, alongside those from domestic manufacturers.

‘Kits not able to detect positive cases’

After receiving Rajasthan’s complaint, the ICMR sought feedback on rapid antibody tests from three more states.

The kits were found to be detecting antibodies in 6-71 per cent of positive cases when their results were confirmed through RT PCR, said Raman Gangakhedkar, the head of infectious diseases at ICMR. 

“This is not a good sign, this variation needs investigation,” he added.

According to Gangakhedkar, the kits are first-generation innovations that are yet crude but will be refined in the future. 

He said the ICMR will send officials from eight institutes to validate the kits on the ground. In case they detect problems, the companies will be asked to take them back, he added. 

“We request the states to not carry out any rapid antibody tests in the next two days,” he said. 

On Monday, Rajasthan Health Minister Raghu Sharma had complained that the kits could only detect 5.4 per cent of the positive cases and “therefore were of no benefit”. The state had reportedly received 30,000 antibody kits from the ICMR and tested them on 168 positive cases.

Global issues with rapid testing kits

The WHO had said on 8 April that all kinds of rapid tests should only be used in research settings until there is more evidence to support their use.

Similarly, earlier this month, there were reports that the UK will seek refunds for millions of rapid diagnostic test kits from Chinese companies after they failed a validation by the University of Oxford. Similar rapid diagnostic tests failures have been reported in Spain, the Czech Republic and Slovakia.