Incidence and Factors Related to Adverse Events Following Immunization for COVID-19 in People who Received Vaccination at Maharat Nakhon Si Thammarat Hospital Service Unit

Abstract

      A retrospective prospective study aimed to study the incidence and factors associated with the occurrence of adverse reactions after vaccination Coronavirus disease 2019 (COVID-19 vaccine). The samples were15,438 people who came to receive vaccinations at the Maharat Nakhon Si Thammarat Hospital service unit from April 6, 2021 to August 31, 2021. Secondary data collection from the COVID-19 vaccine recipient database 2019 (MOPH Immunization center). Descriptive statistics and Multiple logistic regression with adjusted odds ratio (AOR) and 95% confidence interval (95%CI) were used to measure the magnitude of association between an exposure and the occurrence of adverse reactions after vaccination, adjusted for the influence of other variables.

     The results showed that the incidence of adverse reactions within 30 days after vaccination was 31.42 %, with the highest incidence of the Comirnaty vaccine at 51.90%.  The most common adverse reaction was myalgia, 37.37%. In addition, the significant factors associated with the occurrence of adverse reactions after vaccination for Coronavirus disease 2019 were female (AOR = 1.502, 95%CI: 1.392–1.621, p = <0.001). The three younger age group were as follows; 18-29 years (AOR = 2.076, 95%CI: 1.870-2.306, p = <0.001), age 30 – 39 years (AOR = 2.040, 95%CI: 1.848-2.251, p = <0.001), age 40-49 years (AOR =1.531, 95%CI: 1.383-1.696, p = <0.001) and two vaccine types ,AstraZeneca (AOR =2.158, 95%CI: 1.978-2.354, p = <0.001), and Comirnaty (AOR =2.337, 95%CI: 1.949-2.900, p = <0.001).This data can be utilized to provide accurate information to people who are deciding whether or not to get vaccines. This will increase their confidence and awareness of vaccination's safety, as well as provide appropriate medical resources to treat the symptoms of adverse reactions to vaccination.