COVID-19 Neutralizing Antibodies Persist Rate after Vaccination in Correlation with Vaccine type in Some Nasiriyah Vaccinated Citizen

Abstract

Background

Aim:The presence of neutralizing antibodies (NAbs) is an indicator of protective immunity formost viral infections. This study investigated the detection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) neutralizing antibodiesNAbs (IgM & IgG) following vaccination with three common potential vaccines (Pfizer, AstraZeneca and Sino pharm),in Nasiriya city /south of Iraq.

Methods. From September 2021 to April 2022. 158 participants who had completed COVID-19 vaccination (50 persons for each) were recruited and tested using Covid-19 neutralizing antibody kits, for NAbs evaluation.

Results. Majority of the participants were 21–40 years old of age. NAbswereobserved in 100% of enrolled individuals (vaccinated or not) butwithsignificant difference in the IgM and IgG titers in correlate to the vaccine type, but there weren’t with other demographic factors effect.Nine days after second vaccine dose, spike protein neutralizingantibody levels weretwo-fold higher of IgM and 5-fold higher of IgG, exceeding titers of non-vaccinated SARS-CoV-2-naive control.Pfizer vaccine type against COVID-19 gave the highest IgM and IgG titers during the 6 months’ trial, with the lowest declining rate. AstraZeneca vaccine type provided an intermediate IgM and IgG titer with a rapid declining rate, while Sino pharm vaccine offered a low IgM and IgG titers with slowly decreasing rate with time.

Conclusion:the rate of COVID-19 specific antibodies continuation within body aftervaccination, may influencedby several controlling factors, so there is still much to learn about factors affecting permanenceof antibodies after SARS-CoV-2 vaccination.