SARS CoV-2 Antibodies in Cord Blood of Neonates Delivered to Pregnant Mothers Vaccinated for COVID-19

Abstract

Background: The recent novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) pandemic has been responsible for millions of deaths globally. Several vaccines against the SARS-CoV-2 virus have been developed. Objective: To estimate the proportion of newborns who acquire IgG anti-SARS-CoV-2 antibodies from mothers vaccinated against COVID-19. Methods: Eligible study subjects seeking care in the Obstetrics & Gynecology department for delivery were recruited in this cross-sectional analytic study. Demographic and clinical characteristics of the study subjects were noted and around 3–5 mL venous blood was collected from each study participant duo (mother and newborn) to detect IgG antibodies to SARS-CoV2 “S” protein. Results: Over the entire study period, 125 pregnant ladies who were vaccinated with two doses of any COVID-19 vaccine were included in the study. A sizeable proportion (44.0%) of vaccinated pregnant women were seropositive for IgG antibodies to SARS-CoV2 “S” protein. A significantly high number of seropositive newborns (82.8%) were delivered to seropositive mothers as compared to seronegative mothers (OR 41.1; 95% confidence interval 14.6–116.1, p < .0001). Conclusions: The present study reveals that a substantial proportion of newborns acquired SARS-CoV-2 antibodies from their vaccinated seropositive mothers through transplacental transfer.