The rising number of false negative tests for Covid-19, surfacing in the second wave of the pandemic sweeping across India, have become a cause for grave concern. This is being attributed to some new strains of coronavirus that the standard RT-PCR tests are not being able to detect.

There are increasing cases of patients with full-blown symptoms of Covid-19 testing negative. Health experts are of the view that the coronavirus is constantly mutating and some new strains have emerged which may not be detected by the current RT-PCR tests.