the increasing number of COVID-19 vaccines available to the public may trigger hesitancy or selectivity towards vaccination. This study aimed to evaluate the post-vaccination side effects of the different vaccines approved in Germany; Methods: a cross-sectional survey-based study was carried out using an online questionnaire validated and tested for a priori reliability. The questionnaire inquired about demographic data, medical and COVID-19-related anamneses, and local, systemic, oral, and skin-related side effects following COVID-19 vaccination; Results: out of the 599 participating healthcare workers, 72.3% were females, and 79.1% received mRNA-based vaccines, while 20.9% received a viral vector-based vaccine. 88.1% of the participants reported at least one side effect. Injection site pain (75.6%) was the most common local side effect, and headache/fatigue (53.6%), muscle pain (33.2%), malaise (25%), chills (23%), and joint pain (21.2%) were the most common systemic side effects. The vast majority (84.9%) of side effects resolved within 1-3 days post-vaccination; Conclusions: the mRNA-based vaccines were associated with a higher prevalence of local side effects (78.3% vs. 70.4%; Sig. = 0.064), while the viral vector-based vaccine was associated with a higher prevalence of systemic side effects (87.2% vs. 61%; Sig. < 0.001). Females and the younger age group were associated with an increased risk of side effects either after mRNA-based or viral vector-based vaccines. The gender- and age-based differences warrant further rigorous investigation and standardized methodology.

Clinic for Conservative Dentistry and Periodontology School of Dental Medicine Kiel University Arnold Heller Str 3 Haus B 24105 Kiel Germany

Czech National Centre for Evidence Based Healthcare and Knowledge Translation Institute of Biostatistics and Analyses Faculty of Medicine Masaryk University Kamenice 5 625 00 Brno Czech Republic

Department of Oral and Maxillofacial Surgery Justus Liebig University Klinikstrasse 33 35392 Giessen Germany

Department of Oral and Maxillofacial Surgery University of Erlangen Nuremberg Glückstraße 11 91054 Erlangen Germany

Department of Public Health Faculty of Medicine Masaryk University Kamenice 5 625 00 Brno Czech Republic

Institute of Health Information and Statistics of the Czech Republic Palackého náměstí 4 128 01 Prague Czech Republic

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