The council said it was investigating the issue as some states had reported huge variations — ranging between 6% and 71% — in test results from rapid antibody kits which it said was unacceptable and may need to be replaced, which will be a setback to the government’s plan to use rapid tests for surveillance and tracking trends, though not for diagnostics.
On Tuesday morning, Rajasthan — the first state in the country to conduct rapid tests for Covid-19 — decided to stop using the kit any further as it was found that the results were inaccurate and did not correlate with the results of the polymerase chain reaction (PCR) test. This also triggered a reaction across the country with many other states discontinuing the testing.
In a tweet late on Tuesday, Rajasthan chief minister
Ashok Gehlot said: “I had earlier suggested to GOI (government of India) that a centralised mechanism with proper guidelines of quality check may be developed for the procurement of medical equipment. Unfortunately this was not accepted. Had this suggestion been accepted, failure of Rapid Test kits could have been avoided. We have written to ICMR for the same.”
However, well-placed sources said the tests may not be at fault and might not have been correctly used. “The kits are not faulty,” an official familiar with the testing strategy said. “The use of these kits for diagnosis is at fault. The proper test for
Covid is the RT-PCR test. It is possible that states may have resorted to a short-cut in seeing them as diagnostic tests,” he added.
Thanks to this, India’s testing rate has dropped from 35,000-odd on Monday to 27,500 on Tuesday as states are using testing infrastructure for antibody tests. ICMR is expected to issue a detailed clarification soon. There have also been reports that the temperatures needed for the rapid tests have not been observed.
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The kits had arrived last week after several delays and have been sourced from three companies based in China. In the first batch, some 3,00,000 kits arrived close to two weeks after they were due. In all, 6,50,000 are to be delivered with more in the pipeline by way of domestic operations in collaboration with foreign firms and other orders that have been placed. The kits are being sent to states based on their requirements.
There were complaints from states with the kits meant to be used in hotspots and red zones as a supplement to the polymerase tests that are much more reliable but take more time as it’s are a four-stage procedure to be conducted in labs.
“On Monday, we received a complaint from one state about less detection through rapid antibody test kits. So we asked around three states on Tuesday and found that among positive samples of RT-PCR, there is too much variation in rapid antibody tests,” said ICMR’s head of epidemiology and communicable diseases, Dr R R Gangakhedkar. “In some places, 6% to 71% of RT-PCR positive samples were positive,” he added.
ICMR has decided to send eight different teams for testing and validating the kits in the field over the next two days, after which it will issue a fresh advisory on the use of rapid antibody test kits. “If problems are detected in batches, we will tell the company and can ask them to replace the batches,”
Dr Gangakhedkar said, while asking states to halt testing through the rapid antibody kit till then.
While concerns about level of accuracy of rapid antibody tests were raised earlier too, ICMR and the health ministry maintained that the tests were to be used only for surveillance and monitoring of trends. ICMR has recommended only RT-PCR tests for testing individuals who are Covid-19 suspects, which it said was the gold standard.
“This is not a good thing because when such a huge variation is seen, we need to investigate further even if it is the first generation of the test,” Dr Gangakhedkar said. He, however, said rapid antibody test was a new and first-generation test and would require time to develop further and perform better in new diseases like Covid-19.
Highly placed sources in the government told TOI that ICMR had clarified (in government meetings) that rapid test kits show positive reports only after seven days — the period a body needs to generate antibodies that can be detected. They also said that purchases of these kits were made directly by ICMR.
“ICMR was directly involved in procurement of rapid test kits from both China and South Korea. The vendors were approved by the local government,” said a source.
In Rajasthan, a committee submitted its report following a study conducted on rapid tests. “The SMS Medical College submitted its report to us and they found that those who tested positive in the PCR test have been found negative for Covid-19 in the rapid test. When we correlated the results of PCR and rapid tests, we found that only 5.4% were matching. Ideally, the matching should be at least 90%,” said Rajasthan health minister Raghu Sharma.
Maharashtra put a last-minute stop on using the rapid test kits. The state had received 75,000 kits and was planning to carry out tests among healthcare workers and subsequently in hotspots such as Mumbai’s Dharavi. The BMC had plans to start testing medical workers using the rapid kits from Wednesday. Dr Anup Kumar Yadav, commissioner of the National Health Mission, said that they have decided to wait for 48 hours for the ICMR’s new advisory.
West Bengal decided to put rapid tests on hold till it got a clearance from ICMR, Kolkata mayor Firhad Hakim said late on Tuesday. Bengal had tested 78 people on Monday and another 220 on Tuesday.
Punjab, which was amongst the first states to flag the issue of low accuracy, decided not to use kits provided by the central government. To check the accuracy of the kits, Punjab principal health secretary Anurag Agarwal on April 19 got a survey conducted in Mohali and Jalandhar, the worst-hit districts in the state, by testing positive cases. Random sampling among the general public was also done. In both the categories, a majority of samples collected showed false negative and positive results.
In Uttar Pradesh, state surveillance officer for Covid-19 Vikasendu Agarwal said: “UP will put on hold use of rapid kits after ICMR’s observation.” UP had recently used the kits to screen over 10,500 children who returned from Kota. The kits were also used for surveillance in hotspots of Gautam Buddh Nagar.
Gujarat too has put its use on hold. “There are two confirmatory strips — IgM and IgG — in these kits. Both are to turn positive to confirm a case. But in certain cases, only one of the two strips shows results while the other strip fails and hence the case remains inconclusive,” said principal secretary (health) Jayanthi Ravi.
Tamil Nadu, which ordered four lakh rapid antibody testing kits, has put its orders on hold since Saturday. The Tamil Nadu Medical Services Corporation managing director P Umanath said his team was re-negotiating the price and re-evaluating the stock required after the ICMR said the tests cannot be used for diagnostic purposes.
While Assam and Haryana too have suspended use of these kits, states like Madhya Pradesh, Kerala, Andhra Pradesh and Telangana are yet to begin using them.