COVID-19 sero-surveillance report in a metropolitan city of Maharashtra

Introduction: The WHO global research map for COVID-19 and others had recommended population-level sero epidemiological studies to generate data on the levels of infection in populations and recommended containment measures accordingly. In order to understand the extent of COVID-19 infection, as well as efficacy of vaccine administration program, the present was conducted a COVID-19 sero-survey across the city and study in relation to variables limit like demographic, environmental, social factors.To conduct a COVID-19 sero-survey across the city and study in relation to variables limit like demographic, environmental, social factors in study population.Materials and Methods: A total of 1571 subjects were surveyed from the 9 wards of Thane Corporation area. The random sampling method ensured almost equal distribution across these wards. Six different age groups defined to ensure a non-skewed spread across all age groups.Results: Higher seroprevalence is seen in younger age groups. The maximum seropositivity was observed in 30-45 age group and minimum was observed in 06-17 age group. This may be attributed to the non-vaccination. Amongst the fully vaccinated population, 5.2% of participants are non-responder i.e. remains seronegative despite partial or full vaccination.Conclusion: COVID-19 pandemic may continue to attack the mankind till all of us develop a strong immunological defense against it either by natural (clinical and sub clinical) or vaccine induced immunity against COVID-19. This sero-surveillance survey still provides us with accurate baseline figures about different socio-demographic and vaccination coverage factors released with the immunological status of participants. Further, regular surveys are necessary above this baseline seroprevalence survey to study any shift in the seropositivity status and the type of variants, so that timely intervention can be considered.