Prevalence of side-effects associated with the booster dose of Pfizer-BioNTech (BNT162b2) of COVID-19 Vaccine among vaccinated adults in the Eastern province of Saudi Arabia.

Background: Reports of local and systemic side-effects of COVID-19 vaccination may play an important role in public confidence in the acceptance of the COVID-19 vaccine booster dose.

Methods: We conducted a retrospective cross-sectional study among adults living in Eastern Province of Saudi Arabia. A link to the survey was distributed to community members via WhatsApp, SMS, or e-mail. Participants' general and demographic information was also collected, as well as information about any local and systemic side-effects reported following vaccination.

Results: A total of 370/390 (94.87%) of respondents reported one or more side-effects. Pain or redness at the site of injection (88.92%), fatigue (43.78%), body pain fever (37.84%), and headache (15.95%) were the most commonly reported side-effects. Moreover, 2.43% of the participants reported side-effects needed to see a physician; only four were admitted to the hospital. The non-healthcare respondents (n=273 (97.15%), OR (95% CI) = 5.22 (2.02, 13.48, <0.001) were more likely to report side-effects compared to the healthcare related respondents (n=36 (85.71%), OR (95% CI) = 0.25 (0.10, 0.70), =0.013).

Conclusion: According to this study, the Pfizer-BioNTech (BNT162b2) COVID-19 vaccine was safe when given to Saudi Arabian adults. All reported side-effects were mild to moderate. The findings will likely persuade vaccine-hesitant individuals and pessimists to accept booster dose of COVID-19 vaccine.