Safety and Reactogenicity of the ChAdOx1 (AZD1222) COVID-19 vaccine in Vaccinee in Saudi Arabia

AlBahrani, Salma; AlBarraK, Ali; Alghamdi, Othman Ali; Abdullah alghamdi, Mesfer; Hakami, Fatimah H.; Abaadi, Asmaa K. Al; Alkhrashi, Sausan A.; Alghamdi, Mansour Y.; Almershad, Meshael M.; Alenazi, Mansour Moklif; ElGezery, Mohamed Hany; Jebakumar, Arulanantham Zechariah; Al-Tawfiq, Jaffar A.

INTRODUCTION: : The Kingdom of Saudi Arabia was one of the first countries to implement a COVID-19 vaccination program. Here, we estimated the safety and reactogenicity of the ChAdOx1-S vaccine as administered to adults after the first dose. METHODS: : This is a cross-sectional study and included 1592 randomly selected vaccinees from April to May, 2021. Questionnaire was delivered to the vaccinees via phone calls 7 and 21 days after the first vaccine dose. RESULTS: : Of the 1592 vaccinees who had the first dose, the mean age was 37.4 (± 9.6) and 81% were males. Of all the vaccinees, 553 (34.7%) reported an adverse reaction on the first call. The most common symptoms were: pain at the site of injection (485, 30.5%), musculoskeletal symptoms (438; 27.5%), skin rash (307, 19.2%), gastrointestinal symptoms (379, 23.8%) and fever (498, 31.3%). Men were more likely to report fever (76.9% vs. 23.1%; P = 0.005), skin rash (81.1% vs. 18.9%, P = 0.005) and pain at the injection site (77.3% vs. 22.7%, P < 0.0001). Post-vaccine COVID-19 infection was 0.5% and no hospitalization. CONCLUSION: : In this study, we observed no major side effects of the ChAdOx1-S and no reported breakthrough infection during the observation period.