Insights from a Pan India Sero-Epidemiological survey (Phenome-India Cohort) for SARS-CoV2.

To understand the spread of SARS-CoV2, in August and September 2020, the Council of Scientific and Industrial Research (India) conducted a serosurvey across its constituent laboratories and centers across India. Of 10,427 volunteers, 1058 (10.14%) tested positive for SARS-CoV2 anti-nucleocapsid (anti-NC) antibodies, 95% of which had surrogate neutralization activity. Three-fourth of these recalled no symptoms. Repeat serology tests at 3 (n = 607) and 6 (n = 175) months showed stable anti-NC antibodies but declining neutralization activity. Local seropositivity was higher in densely populated cities and was inversely correlated with a 30-day change in regional test positivity rates (TPRs). Regional seropositivity above 10% was associated with declining TPR. Personal factors associated with higher odds of seropositivity were high-exposure work (odds ratio, 95% confidence interval, p value: 2.23, 1.92-2.59, <0.0001), use of public transport (1.79, 1.43-2.24, <0.0001), not smoking (1.52, 1.16-1.99, 0.0257), non-vegetarian diet (1.67, 1.41-1.99, <0.0001), and B blood group (1.36, 1.15-1.61, 0.001).
Competing Interests: SN, VS, RU, NB, RK, AB, SP, SP, RK, BR, KT, MA, GC, AL, SK, SM, MM, MS, SK, AS, BT, MV, GV, SV, AA, DG, PH, MP, GS, RV, AP, VA, AM, RS, AR, SA, PK, SV, HS, AK, RJ, AT, DP, AS, JK, VK, AM, IG, GR, PS, RC, GC, PK, RY, SS, DS, SS, PB, SA, VS, SV, DS, SS, SV, ST, FF, AS, AS, BS, MS, YP, VH, VP, DS, NT, PC, SM, DG, JS, SR, BK, KK, SG, PJ, RC, VJ, NK, DG, GT, US, PS, SC, RK, PG, AT, DS, RR, AD, MK, DS, MD, SD, RJ, AP, SM, AK, VW, RY, AK, MB, AC, SK, KK, SP, JK, NS, TP, PM, WR, PB, DO, RS, EB, RS, AN, PV, AP, AV, KC, SD, YM, VA, SD, AA, DD, SS No competing interests declared
(© 2021, Naushin et al.)