International Journal of Chemical and Biochemical Sciences (ISSN 2226-9614)[/vc_column_text][/vc_column][/vc_row]

VOLUME 29(24) (2026)

The Side Effects Associated with COVID-19 Vaccines: A Systematic Review and Meta-analysis

Ibrahim Kamil Ibrahim Luttfi¹, Shaimaa Ahmed Attia Amer², Abeer Elsayed Ameen³

¹Public Health and Community Medicine Department, Faculty of Medicine, Managil University and Arab College of Applied Sciences, Egypt.

²Occupational Medicine and Environmental Health Department, Faculty of Medicine, Suez Canal University, Egypt.

³Public Health and Community Medicine Department, Faculty of Medicine, Suez Canal University, Egypt.

Abstract

               Coronavirus disease 2019 (COVID-19) vaccines have been deployed extensively worldwide. While post-vaccination side effects are common, they frequently generate public concern, impacting vaccine confidence and uptake despite proven vaccine efficacy. Consequently, we undertook this systematic review and meta-analysis to evaluate and compare the prevalence and patterns of post-vaccination side effects across available COVID-19 vaccine platforms (mRNA, viral vector, and inactivated vaccines), focusing on Pfizer-BioNTech, Oxford-AstraZeneca, and Moderna. This study was a systematic review and meta-analysis of proportions, conducted according to the PRISMA principles. Risk of bias was assessed with the Newcastle-Ottawa Scale for observational studies. Open Meta [Analyst] was used to perform statistical analysis and generate pooled estimates using a random-effects model. Heterogeneity was measured using the I² statistic. In the quantitative synthesis, 11 studies with a total of 87,105 participants were included. All included studies were cross-sectional, and most were assessed as having a moderate risk of bias. The most commonly reported local adverse event was pain at the injection site, with the highest rates observed after mRNA vaccines, especially Moderna and Pfizer-BioNTech. Regarding systemic adverse effects, chills (19.3%), fatigue/weakness (17.4%), headache (14.7%), fever (12.8%), and nausea (12.8%) were the most frequently described. Viral vector vaccines had the highest pooled prevalence for systemic side effects (28%; 95% CI: 18%–43%) compared to mRNA vaccines (15%; 95% CI: 11%–19%) and inactivated vaccines (12%; 95% CI: 8%–17%), with a statistically significant subgroup difference (p = 0.0008). Overall, the findings support an acceptable safety profile for these COVID-19 vaccines; however, there was significant heterogeneity between studies, and caution is required when interpreting results given that larger standardized studies are pending.

Keywords: COVID-19 vaccines; Pfizer-BioNTech; Oxford-AstraZeneca; Moderna; side effects.

Review article             *Corresponding Author, e-mail: ibrahim.kamil24@gmail.com; Doi # https://doi.org/10.62877/5-IJCBS-26-30-24-5

Submitted: 09-09-2026; Accepted: 09-10-2026; Published: 10-10-2026