LocalCircles survey finds atleast 40% undercounting in Delhi-NCR daily COVID cases reported in April

May 3rd, 2022, New Delhi: The RT-PCR test and Rapid Antigen Test (RAT) have become important to trace if an individual has been infected by COVID. Per ICMR’s advisory on ‘Purposive Testing Strategy for COVID-19’, only symptomatic individuals may get tested with RT-PCR, which can be taken in a laboratorial setting and the result can be obtained within 8 hours. Whereas the rapid antigen test has become popular among citizens as it can be taken in home settings and the result can be obtained within just 10 minutes.

As COVID cases rose again in Delhi-NCR after the mask mandate was removed from April 1st, the test positivity rate (TPR) rose from under 1% to 5% within the first 15 days of the month. Delhi has been reporting between 1000 to 1600 cases a day and yesterday reported a TPR of 6.42%. While this has been happening, residents of Delhi and NCR cities of Gurugram, Noida, Ghaziabad and Faridabad have been writing on LocalCircles about how most people in their family and friends are just opting for the at-home antigen test and are not taking the RT-PCR test anymore. Positive cases that arise from these at-home tests are not reported anywhere and the government data does not count them in official case figures. However, a lot of government containment measures and restrictions are based on the test positivity rates. The concern is that if a lot of symptomatic positive residents decide to take the at-home rapid antigen test, even the daily TPR could be significantly understated as these individuals aren’t taking the RT-PCR test or part of any antigen test camps organised by the government in community locations like markets, schools, etc.

To understand the magnitude of undercounting in the daily reported cases, LocalCircles conducted a study, which received more than 16,000 responses from citizens located in all districts of Delhi-NCR. 62% respondents were men while 38% respondents were women.

39% Delhi-NCR families had 1 or more individuals who got tested for COVID in April

The question in the survey asked, “In the last 1 month when you or family members had some symptoms and needed a COVID test (non-travel), what type of test did you undertake?” In response, 7% said “RT-PCR several times”, another 7% said “RT-PCR once/twice”. Breaking down the poll, 11% said “Rapid Antigen Test multiple times”, and 7% said “Rapid Antigen Test once/twice”. There were also 7% saying “Mainly Rapid Antigen Test & RT-PCR test once/twice”. The majority, 57% said “Did not undertake any COVID test at all in the last 30 days”. 4% couldn’t say. This question in the survey received 16,856 responses.

Only 1 in 3 residents of Delhi-NCR took a RT-PCR test in the last 30 days while majority opted for at-home antigen testing pointing to sizable undercounting of daily caseloads

If only those residents of Delhi-NCR who took the COVID test are analysed, the survey provides another perspective on the issue. In the 7,248 individuals who confirmed taking the COVID test are looked at by the test type taken, the findings suggest that 17% of them took “RT-PCR several times”, and 16% took “RT-PCR once/twice”. 26% took “Rapid Antigen Test multiple times”, and 16% took “Rapid Antigen Test once/twice”. 16% took “Mainly Rapid Antigen Test & RT-PCR test once/twice”. 9% couldn’t say which test was taken by them.

In summary, 39% of Delhi-NCR families had 1 or more individuals who got tested for COVID in April. Of those Delhi-NCR residents who took a COVID test in the last 30 days, only 33% of them took the RT-PCR test. 42% of those who had symptoms and took the COVID test took the at-home rapid antigen test. Another 16% primarily took the at-home rapid antigen test and then an RT-PCR test. With 42% of Delhi-NCR residents who took the at-home rapid antigen test post symptoms not being in the official record, the numbers are clearly understated. Then, of course, there are those who despite having symptoms never took any test.

The key here is for all District Administrators, State Governments and Central Government to understand that the daily case counts reported could be understated by a magnitude of 40-60% and the same could go up further as antigen test kits reach every corner of India. If the tracking of COVID is important, it is critical for ICMR and the Ministry of Health to institute a process where the test results are mandatorily connected to a mobile app or number and uploaded.