Nearly 11% of 32,903 coronavirus patients in Delhi, who tested negative through rapid antigen tests, were found to be infected with Covid-19 when they took a real-time reverse transcription polymerase chain reaction, or an RT-PCR test, between September 1 and November 7, PTI reported on Sunday.
In order to effectively curb the spread of coronavirus infection, the Union Health Ministry had in September asked all states and Union Territories to mandatorily retest all symptomatic cases, who were found to be Covid-19 negative in rapid antigen tests, through RT-PCR, so that no positive case is missed. Antigen tests have a high rate of false negative results.
In Delhi, out of the 56,862 symptomatic patients whose test results came negative through a rapid antigen test, 32,903 were tested again through RT-PCR. Out of these, 3,524 were found to be Covid-19 positive, a Right to Information query filed by PTI has revealed.
The case positivity rate in RT-PCR tests, which is…