More Than Three-Fourths of AstraZeneca (ChAdox1 COV-19) COVID-19 Vaccinated Individuals Develop Post Immunization Adverse Event in Northwest Ethiopia

Ethiopia was using the ChAdOx1 COV-19 vaccine, and health professionals were targets of the first phase of the vaccination strategy. Evidence on the adverse events following immunization (AEFI) was barely available. The study aimed to assess the magnitude and associated factors of adverse events following ChAdOx1 COV-19 immunization among health professionals of the University of Gondar Specialized and Comprehensive Hospital, 2021.

An institution-based cross-sectional study was conducted among health professionals of the University of Gondar Comprehensive and specialized referral hospital. All health professionals who took the ChAdOx1 COV-19 vaccine in the 1st phase were surveyed. A total of 314 health professionals who took the ChAdOx1 COV-19 vaccine were included. The EpiData version 4.6.0.0 and Stata 16 were used for data entry and analysis, respectively. A binary logistic regression was used to identify statistically significant factors associated with AEFI. Chi-square and multicollinearity assumptions were tested. A p-value <0.2 and 0.05 were used as cut-off values of significance in the bi- and multivariable logistic regression models, respectively. An adjusted odds ratio (AOR) with 95% CI was reported for statistically significant variables.

Among 314 study participants, 263 of them had at least one mild to severe AEFI of ChAdOx1 COV-19 with a prevalence of AEFI of 83.76% (95% CI: 79.23, 87.46). The commonest AEFI observed were injection site tenderness (n=198/263), fatigue (114/263), headache (n=107/263), and muscle pain (n=85/263). Females (AOR=2.75, 95% CI: 1.15, 6.58), and participants who felt the vaccine was unsafe (AOR=2.84, 95% CI: 1.03, 7.85) were having nearly three times more odds of AEFI immunization as compared to males and those who felt the vaccine was safe, respectively.

Adverse event following immunization has been a public health problem in Northwest Ethiopia. Being female and having a feeling that the vaccine is unsafe were statistically significantly associated with AEFI.