A joint study carried out by WHO and All India Institute of Medical Sciences (AIIMS), Delhi, has found a high SARS-CoV-2 sero-positivity rate among children in India which considerably eases concerns over the fact that if there is a third wave of the Covid-19 pandemic, children would be more vulnerable to coronavirus infections than other age groups.
Sero-positivity refers to the body's ability to trigger a natural immune response to fight viruses.
The study, conducted with a sample size of 10,000 across five states, was approved by the Institutional ethics committee of AIIMS and other participating institutions. Out of 4,509 participants for whom data is available, 700 were less than 18 years of age and 3,809 were aged 18. This is a midterm analysis. And more results are expected to come in the next two to three months.
The places chosen for the study include Delhi urban, Delhi rural, Bhubaneswar, Gorakhpur, and Agartala.
Data collection for the study was done between March 15, 2021 and June 10, 2021. According to the research team, ELISA kits were used to measure the total serum antibody among participants.
The study concludes : "SARS-CoV-2 sero-positivity rate among children was high and were comparable to the adult population. Hence, it is unlikely that any future third wave by prevailing Covid- 19 variant would disproportionately affect children two years or older.”
• Seroprevalence (level of antibodies in a population) was 74.7 per cent in South Delhi's densely-populated resettlement colony even before the second wave hit.
• Seroprevalence was 59.3 per cent among children in Faridabad (NCR).
• Findings from the study also suggest that the areas surveyed in Delhi and Faridabad may have higher seroprevalence after the intense second wave.
• Seroprevalence in the rural district of Gorakhpur in Uttar Pradesh was found to be 87.9 per cent.
• "Overall, more than half (62.3 per cent) of the rural population surveyed showed evidence of past infection," revealed initial findings of the study.
• The study found that seroprevalence was lowest among children at 51.9 per cent in Tripura.
"These areas in Delhi and NCR (Faridabad) may have higher seroprevalence after the intense second wave. Probably, these levels of seroprevalence may be protective against any possible third wave," said Dr Puneet Misra, Professor of Community Medicine at AIIMS.
"In congested urban areas of Delhi, since children already have high sero-prevalence, opening schools, may after all not be a very risky proposition,” the survey said.
The survey established that rural areas have been mostly affected in the second wave, which means more chances of herd immunity The accelerated peaks and precipitous decline in Covid-19 cases in both Delhi and Uttar Pradesh could be explained partially by these findings.