Adverse Events Following Immunization of ChAdOx1 nCoV- 19 Vaccine Among Health Care Workers of a Tertiary Care Hospital of North India

Abstract Background Adverse events following immunization (AEFI) of COVID-19 vaccines among healthcare workers (HCW) of North India remains underexplored. The prevalence of AEFI is usually directly related to willingness to get vaccinated among general population. In this study we report prevalence of AEFI and factors associated with the AEFI of the ChAdOx1 nCoV-19 vaccine (Covishield) among HCW of a tertiary care hospital of North India. Methods A cross-sectional study conducted in the month of June & July, 2021, HCW (N = 203) of 18 years and above who had received at least the 1st dose of Covishield vaccine were included after taking their informed consent. A semi-structured, pre-validated and pre-tested questionnaire was used to collect information. The Questionnaire was divided into five sections: socio-demographic profile, behavioural characteristics, past medical history, COVID-19 awareness and past infection and COVID-19 vaccine related information. Data was collected through interview schedule. Chi-squared test was applied to check the association of different factors with AEFI. Results In our study 73.89% participants suffered from at least one AEFI after 1st dose of vaccine, while 48.66% had at least one AEFI after 2nd dose. Females reported significantly high AEFI compared to males for both the doses of Covishield vaccine (p = 0.001, 0.000). We found significant association between occurrence of AEFI and occupation (1st dose p = 0.015), substance abuse (1st dose p = 0.002), diet (1st dose p = 0.016), and allergy (1st dose p = 0.027). Other significant findings were headache among HCW ≥ 40 years of age (2nd dose p = 0.034), systemic AEFI in participants with comorbidity (1st dose p = 0.020). Conclusions More AEFI were reported after first dose as compared to the second dose. AEFI were more among females after both the doses. Occupation, substance use, diet, and history of allergy were significantly associated with occurrence of AEFI. Awareness should be created among general population about the mild AEFI to reduce the vaccine hesitancy. There should be provision of follow-up of vaccinated person for early detection of possible AEFI. Proper advice should be given to vaccinated candidates about adverse events of self-medication after AEFI.