Background: The incidence of adverse events following the administration of COVID-19 vaccination was significantly related to the total number of doses administered. This study aimed to assess the association between COVID-19 vaccines and the risk of adverse effects occurrence among Zagazig University Personnel.

Methods: This cross-sectional retrospective study included 1041 participants, who have taken 1 or more of COVID-19 doses. They were divided into those who had taken either Pfizer, AstraZeneca, Sinopharm, Sinovac, Moderna, Johnson, or Sputnik vaccine. Data were collected from using a designated questionnaire, adverse reactions were estimated.

Results: There is a significant difference between vaccine type and adverse effects of different vaccines (like local pain, fever, headache, myalgia, and chills) among the studied group who received the first dose, 2nd dose, or 3rd doses of vaccines, between vaccine type and abdominal adverse effects (nausea, vomiting, diarrhea or abdominal pain), between vaccine type and all of the following respiratory( cough, runny nose, sore throat, dyspnea), cardiac adverse effects (palpitations), abdominal adverse effects of different vaccines among the studied group who received the 1st or 2nd or 3rd doses of different types of vaccines (with a p-value of <0.001 for all significant previous differences). People who received Sinopharm had the highest vaccine with no or minimal side effects followed by Sinovac.



Conclusion: Vaccinations against COVID-19 come with some mild side effects. Safest vaccine was Sinovac, dangerous side effects were associated found after Pfizer vaccine as dyspnea and chest pain while the vaccine accompanied by many side effects was AstraZeneca.