COVID-Kavach-Based Seropositivity in the General Population of Ahmedabad: Just Before the Start of the Vaccination for the Elderly in India

Abstract

BackgroundThe present study was carried out in succession of three serosurvey studies carried out during 2020 in Ahmedabad with an objective to estimate the seroprevalence of immunoglobulin G (IgG) antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) in Ahmedabad city so as to scientifically understand the pandemic progression. MethodsPolio booth-based stratification was followed for the population-based stratified sampling among the general population of Ahmedabad. The seroprevalence was compared with various factors for valid and precise predictions regarding the immunity status of the population. ResultsAs on February 2021, the seroprevalence for IgG antibodies against SARS-CoV2 in the general population of Ahmedabad was 27.92% (95% confidence interval 27.06-28.80), much below the minimum desired for herd immunity. Comparison of seropositivity with age groups showed higher seroprevalence with increasing age groups. Seroprevalence was higher among males (29.08%) than females (27.01%) and the difference was statistically significant (Z=2.30, P=0.02). Calculating the seropositivity among the subcategories, cases had a seropositivity of 64.90% and family contacts had a seropositivity of 28.00%. Seronegative cases indicate the possibility of absent, undetectable, or disappearing IgG antibodies. Seropositivity of 37% among the vaccinated individuals may be related to dose and duration of vaccination, as the COVID vaccination had started just before the present study and none had completed 14 days after the second dose. ConclusionsThe low level of IgG antibodies against SARS-CoV2 using the COVID-Kavach test kit in the general population of Ahmedabad city of India, as on February 2021, before the start of COVID vaccination for the general population suggests that the preventive measures be strongly followed for continued control of the pandemic situation at least till majority of the population is effectively covered with vaccination.

Seroprevalence of SARS-CoV-2 antibodies in the county town of Slovakia – a pilot study from the Trencin city

“…Such knowledge at the level of institutions, regions or entire countries can be very useful for the management of anti-pandemic measures. Therefore, it is not surprising that the results of such seroepidemiological studies are presented in dozens of scientific publications (Anda et al, 2022;Fernández-Rojas et al, 2022;Goldfarb et a.l, 2022;Lewin et al, 2022;Mahallawi et al, 2022;Mercado-Reyes et a.l, 2022;Olariu et al, 2022;Prakash et al, 2022;Prguda-Mujic et al, 2022).…”