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

Front Immunol. 2021 Dec 1:12:794642. doi: 10.3389/fimmu.2021.794642. eCollection 2021.

Abstract

Background: The 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.

Methods: A 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).

Results: Among 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.

Conclusion: Participants 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.

Keywords: AstraZeneca; Pfizer; Saudi Arabia; immunogenicity; reactogenicity; vaccines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibody Formation / immunology
  • COVID-19 / diagnosis
  • COVID-19 / epidemiology
  • COVID-19 / prevention & control*
  • COVID-19 / virology
  • COVID-19 Vaccines / immunology*
  • COVID-19 Vaccines / standards*
  • Cross-Sectional Studies
  • Factor Analysis, Statistical
  • Female
  • Host-Pathogen Interactions / immunology
  • Humans
  • Immunization, Secondary
  • Immunogenicity, Vaccine*
  • Immunoglobulin G
  • Male
  • Middle Aged
  • Online Systems
  • Public Health Surveillance
  • SARS-CoV-2 / immunology*
  • Surveys and Questionnaires
  • Vaccine Efficacy*

Substances

  • COVID-19 Vaccines
  • Immunoglobulin G