Data indicates that nearly 11 per cent of those with symptoms who tested negative in Delhi for Covid-19 in rapid antigen tests were found infected in RT-PCR tests. The data in question corresponds to 56,862 symptomatic patients who tested negative in rapid antigen tests in Delhi between September 1 and September 7.
Out of these 56,862 symptomatic patients, 32,903 were tested again using RT-PCR tests, which are the gold standard for coronavirus testing. Of the 32,903, as many as 3,524 were found positive for Covid-19, according to an RTI reply received by news agency PTI.
In September of this year, the Union Ministry for Health and Family Welfare (MoHFW) directed all states and Union Territories to retest all symptomatic individuals who test negative for Covid-19 in rapid antigen tests. The retests must be conducted using RT-PCR tests, the ministry had stated.
For RT-PCR, the positivity rate in Delhi was 20.97 per cent in the month of September. The same, for rapid antigen tests, was 4.77 per cent, reported news agency PTI. In September, 4,597 out of 27,533 symptomatic individuals who tested negative for Covid-19 in rapid antigen, were retested. Of these, only 623 were found positive for the infection in RT-PCR.
Similarly, the positivity rate for rapid antigen tests was 4.58 per cent and 16.76 per cent for RT-PCR in Delhi in October. As many as 26,316 symptomatic cases tested negative in rapid antigen in October. Out of these, 24,737 were retested using RT-PCR and the samples of 2,300 were found to be infected.
Data corresponding to the period between November 1 and November 7 put the positivity rate for RT-PCR in Delhi at 27.2 per cent and for rapid antigen tests at 8.16 per cent. During this period, 4,013 symptomatic individuals tested negative in rapid antigen. As many as 3,569 were retested using RT-PCR and 2,300 tested positive for the novel coronavirus.