Systemic COVID-19 vaccines Adverse Events Following Immunizations and Their Associated Factors: A Comparative Study Using Iraqi Consumers' Self-Reported Data: An International Journal of Medical Toxicology and Drug Experience

ABSTRACT

Introduction: Three types of COVID-19 vaccines were deployed in Iraq;PfizerBioNTech, AstraZeneca, and Sinopharm. Spontaneous self-reported safety data received directly from consumers was an important source of COVID-19 vaccine reporting sources for the first time in Iraq. Objective: To study the common systemic AEFIs and factors influencing them, using self-reported data by Iraqi consumers vaccinated with different COVID-19 vaccine types. Methods: As a part of the national plan for COVID-19 vaccines safety surveillance, an online self-assessment form was designed by the national pharmacovigilance center for the public consumers across the country. The form was quadrilingual and captures the necessary information for a valid AEFI report. Demographic data, contact details, vaccination details, adverse event information, and medical history were collected. To facilitate the filling process and standardize the answers, a list of predefined common short-term AEFIs were included as a checklist, in addition to a free text for other unlisted AEFIs. A retrospective cross-sectional study using the collected responses from April, 2021 until April, 2022 was performed. Data was validated and cleaned. Analyses was performed using SPSS software version 26. Selected common short-term AEFIs were analysed. The incidence of these AEFIs were compared between vaccine types using chisquare test. Moreover, predictors of reporting these AEFIs were explored using binary logistic regression for each vaccine type. Results: A total of 2843 report were included, 62.0% of them were male. The age mean was 36.33 (SD ± 12.2). The participants were more likely to report after the 1st dose (79.4%). AstraZeneca vaccine was found to produce the highest number of AEFIs per report, 4.31 (SD ± 2.4). AstraZeneca and PfizerBioNTech were significantly associated with a higher incidence of multiple AEFIs as compared with Sinopharm (fatigue, joint pain, headache, fever, and chills). PfizerBioNTech vaccine was associated with 71 out of the 76 reported lymph nodes AEFIs. Factors that were significant predictors of higher reporting of systemic AEFIs were;for PfizerBioNTech (female gender, increased dose number, and increased likelihood of previous COVID-19 infection);AstraZeneca (younger age, female gender, and increased likelihood of previous COVID-19 infection);and in case of Sinopharm (younger age, and female gender) Conclusion: The results showed that AstraZeneca and Pfi-zerBioNTech vaccines were associated with more AEFIs than Sinopharm. Predictor factors of AEFIs include;female gender in all vaccines;the presence of previous COVID-19 infection in both PfizerBioNTech and AstraZeneca vaccines;second dose in PfizerBioNTech;and younger age for both AstraZeneca and Sinopharm.