COVID‑19 vaccination and IgG and IgA antibody dynamics in healthcare workers

Abstract

Given the current outbreak of coronavirus disease 2019 and the development and implementation of mass vaccination, data are being obtained by analyzing vaccination campaigns. in the present study, 69 healthcare workers who were exposed to patients with severe acute respiratory syndrome coronavirus-2 were monitored for specific immunoglobulin (Ig)G and IgA levels at different time periods. Prior to vaccination, after the first round of vaccination at 21 days (when the second dose of vaccine was administrated) and 24 days after the second round of vaccination, with an mrna-based vaccine. The basal igG and iga levels in previously infected subjects and non-infected subjects notably differed. Vaccination increased the igG and iga levels after the first dose in most subjects from both groups, the levels of which further increased following the second round of vaccination. The associations between igG and iga levels following the first and second rounds of vaccination demonstrated that in the entire vaccination group, regardless of prior exposure to the infectious agent, the increment and levels of igG and iga were similar. Thus, the levels upon vaccination were statistically similar irrespective of the starting base line prior to vaccination. in the present study, seroconversion was achieved in all subjects following the second round of vaccination, with similar antibodies levels.

Association between Immunoglobulin G Levels and Adverse Effects Following Vaccination with the BNT162b2 Vaccine among Japanese Healthcare Workers

“…This study showed that age was correlated with the amount of anti-SARS-CoV-2 IgG and that IgG levels were higher in younger participants. This may be related to the viability of immunity in the younger population compared with that of older populations, which has been shown in previous studies on other vaccines [ 37 , 38 ]. Younger individuals tend to have more T and B cells related to adaptive immunity and active toll-like receptor reactions, which have a greater association with higher IgG levels among younger individuals than older individuals [ 37 , 39 ].…”

“…The second dose can trigger systemic inflammation, and recipients with strong immunity are more likely to experience systemic symptoms. Previous studies have reported the association between the presence of adverse reactions and the IgG titer [ 33 , 37 ]. However, they did not clearly show the association between concrete adverse effects and IgG titers.…”

Immune response (IgG) following full inoculation with BNT162b2 COVID‑19 mRNA among healthcare professionals

“…However, even though some studies have suggested that IgG titers in vaccinated individuals decline over time, the exact rate of this decline in IgG titers or the critical titer level up to which they can still be considered as adequately protected from infection and disease, remain unclear ( 38 ). At this point, it should be emphasized that the immune system may produce a series of antibody variants, each with a different neutralizing capacity, depending on the exact target-epitope ( 39 - 42 ).…”

“…Of note, a significant decrease in antibody titers was observed at 3 months compared with the peak response, with the antibody response being higher in seropositive compared with initially seronegative participants ( 41 ). A second study was also performed, enrolling a homogenous healthcare workers group in Romania, in an attempt to investigate the immunity status of subjects having received the BNT162b2 mRNA COVID-19 vaccine as well ( 42 ). In this framework, it was found that following the first vaccination dose, the IgG levels in non-infected subjects exhibited an increase of ~12-fold in males and one of ~11-fold in females; however, following the second round of vaccination, the IgG levels increased 1.33-fold in males and 2.11-fold in females, when compared with those after the first dose ( 42 ).…”

“…A second study was also performed, enrolling a homogenous healthcare workers group in Romania, in an attempt to investigate the immunity status of subjects having received the BNT162b2 mRNA COVID-19 vaccine as well ( 42 ). In this framework, it was found that following the first vaccination dose, the IgG levels in non-infected subjects exhibited an increase of ~12-fold in males and one of ~11-fold in females; however, following the second round of vaccination, the IgG levels increased 1.33-fold in males and 2.11-fold in females, when compared with those after the first dose ( 42 ). Importantly, in that study, the most prevalent adverse effects observed were pain at the injection site and flu-like symptoms, which are in accordance with the findings of the present study.…”