The primary reason for the false negative tests among covid-19 patients these days could be attributed to error by lab technicians who may be having a sharply increased workload in the second wave, though some test kits may be missing mutant strains, said Mylab Discovery Solutions managing director Hasmukh Rawal.
To tackle that, India’s largest manufacturer of covid-19 RT-PCR test kits is working to increase automation in covid-19 tests and reduce the errors in results.
“Most of the labs are either on manual or on semi-automated platforms for performing the tests. That is a limiting factor because you need human expertise and availability to do the test. Currently, we are seeing many errors in reporting as well… The second wave has come out of nowhere. Cases are increasing and capacity building of personnel cannot happen overnight. If automation is not in place, there will be fatigue and errors,” Rawal said.
Delays in testing and errors in test results are primarily because of shortage of personnel to handle the equipment, he said. However, a major concern around testing results this month has been false negative results, where patients showing symptoms of covid-19 tested negative in RT-PCR tests, caused by mutations in the virus that evaded detection by test kits.
There may be some kits that may not be able to detect mutant strains of the novel coronavirus, but most RT-PCR test kits, including theirs, were designed to detect multiple regions of the RNA sequence, thus reducing the likelihood of missing strains that have mutation in one of the regions, Rawal said.
Most of the mutations in the virus are happening in the spike protein gene of the virus, while Mylab kits focus on three genes, none of which are a spike protein gene. The company’s test kits focus on the ORF, N and E genes of the virus, which makes him confident that the kits are not causing the false negative results, Rawal said.
The US Food and Drug Administration in an updated note on 30 March said that clinical laboratory staff and healthcare providers who use molecular tests such as RT-PCR should be aware that genetic variants of the virus arise regularly and false negative test results can occur. They asked healthcare workers to consider negative results in combination with clinical observations, patient history, and epidemiological information.
There is no shortage of test kits in the country and they are running at 50% capacity and meeting demand now even when the cases are soaring, Rawal said. Mylab is producing around 300,000 test kits per day, while its capacity is 700,000 kits per day.
There are more than 300 manufacturers of RT-PCR test kits in the country whose products have been found to be satisfactory by the Indian Council of Medical Research, the government agency’s website showed.
India reported nearly 300,000 new cases on Tuesday and conducted 1.64 million tests, data on covid-19india.org showed.