Reactogenicity and Immunogenicity of the Pfizer and AstraZeneca COVID-19 Vaccines

Abstract

BackgroundThe relationships of the coronavirus disease 2019 (COVID-19) vaccination with reactogenicity and the humoral immune response are important to study. The current study aimed to assess the reactogenicity and immunogenicity of the Pfizer and AstraZeneca COVID-19 vaccines among adults in Madinah, Saudi Arabia.MethodsA cross-sectional study, including 365 randomly selected adult Pfizer or AstraZeneca vaccine recipients who received a homologous prime-boost vaccination between February 1st and June 30th, 2021. Data of height and weight were collected to assess the weight status of percipients. An evaluation of seropositivity for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies was assessed using enzyme-linked immunosorbent assay (ELISA).ResultsAmong the participants, 69% (n = 250) reported at least one vaccine-related symptom. Pain at the injection site was the most frequently reported vaccine-related symptom. The mean total score for vaccine-related symptoms was significantly higher among participants who received the AstraZeneca vaccine, women, and participants with no previous COVID-19 infection (p < 0.05). Spike-specific IgG antibodies were detected in 98.9% of participants after the receipt of two vaccine doses, including 99.5% of Pfizer vaccine recipients and 98.3% of AstraZeneca vaccine recipients. Significantly, higher proportions of participants in the <35-year age group developed a humoral immune response after the first vaccine dose compared with the participants in other age groups.ConclusionParticipants who received the Pfizer COVID-19 vaccine reported fewer vaccine-related complications compared with those who received the AstraZeneca COVID-19 vaccine, but no serious side effects were reported in response to either vaccine. Health status and age were factors that may influence COVID-19 vaccine effectiveness for the generation of antibodies against the SARS-CoV-2 spike protein.

Short-Term Adverse Events and Antibody Response to the BNT162b2 SARS-CoV-2 Vaccine in 4156 Health Care Professionals

“…Other studies failed to identify a correlation between adverse events and the IgG titers one month following the BNT162b2 vaccination, but the same authors identified sex and body weight as predictors of the incidence of adverse events [ 20 ]. Our data confirm that female gender and younger age are significantly associated with adverse events, and this may reflect the more efficacious immune response observed in women for SARS [ 21 ] and other vaccines [ 22 ], particularly at a younger age. Among adverse events, lymphadenopathy has been observed in 78.4/100,000 subjects after the SARS-Cov-2 vaccination, more frequently axillary and unilateral [ 23 , 24 ].…”

A potential association between obesity and reduced effectiveness of COVID‐19 vaccine‐induced neutralizing humoral immunity

“…Some previous studies had obese individuals among their study population, but these studies did not intensively investigate whether obesity affects COVID‐19 vaccine effectiveness. 24 , 25 , 26 , 27 , 28 Moreover, immunoassays that only determine the presence of anti‐SARS‐CoV‐2 antibodies, but do not assess their neutralizing activity, were utilized in most of these studies. Hence, we aimed to investigate the effectiveness of various S‐based COVID‐19 vaccines in inducing anti‐S IgG antibodies among individuals with various classes of obesity (class I, II, III, and super obesity).…”

Delayed antigen-specific CD4+ T-cell induction correlates with impaired immune responses to SARS-COV-2 mRNA vaccination in the elderly

“…Although most studies indicate that AEs decrease with age, the associations identified between AEs and antibody responses are largely based on studies involving small cohorts and/or differences in analytical strategies (21)(22)(23)(24)(25)(26)(27). Furthermore, studies have not addressed whether T-cell responses correlate with AEs.…”

“…Notably, AEs have been more frequently observed after the second dose and with higher severity than after the first dose (14), which strongly suggested that AEs are a consequence of immunological memory induced by the adaptive immune system. However, previous reports did not reach a consensus concerning the association between AEs and vaccine-induced immune reactions, such as antibody production, likely due to the small cohorts used in the studies and variations in how AEs were defined (21)(22)(23)(24)(25)(26)(27). Moreover, most studies examined the associations of AEs with antibody levels and/or neutralizing activity but not with T-cell responses, which can result in the production of cytokines and thus cause systemic effects.…”