Exploring the Incidence and Time to Onset of Side Effects Associated with COVID-19 Vaccine

Rakesh Kumar  Saro; Jayden L  Bhutiya; Binu  Upreti

doi:10.18502/jbe.v11i2.20554

Rakesh Kumar Saro School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India.
Jayden L Bhutiya School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India.
Binu Upreti School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India.

DOI: https://doi.org/10.18502/jbe.v11i2.20554

Keywords: COVID-19; Side effects; Survival analysis; Incidence; Log-logistics

Abstract

Introduction: Close monitoring of side effects and their time-to-onset following COVID-19 vaccination is essential toensure vaccine safety and maintain public confidence. The study aims to find the incidence, time of side effects, and factorsresponsible for the COVID-19 vaccine.

Methods: A cross-sectional design was used to collect data from 716 recipients of the first COVID-19 vaccine dose at SikkimManipal University, Sikkim, using a validated, self-administered questionnaire. Survival analysis was applied to find theincidence, time, and causes of side effects.

Results: Of the participants, 79.5% experienced at least one side effect, with pain at the vaccination site (73.8%) and fever(65.2%) being the most frequently reported. Maximum side effects occurred within 12 hours of vaccination. Among thesurvival models evaluated, the log-logistic model demonstrated the best fit for characterizing the time to symptom onset.The analysis revealed that age (Hazard Ratio [HR] = 1.51), education level (HR = 2.28), and use of prior medication (HR =1.48) were significant risk factors for post-vaccination side effects.

Conclusion: This study highlights the importance of early monitoring of side effects following COVID-19 vaccination toensure vaccine safety and maintain public confidence. The finding indicated that most side effects occurred within 12hours of vaccination. Among the models assessed, the log-logistic survival model demonstrated the best fit for modeling thetime to onset of vaccine side effects. Older age, lower education, and use of prior medication were identified as significantpredictors of the post-vaccination side effects. These findings support the early monitoring and personalized care to ensurevaccine safety, health, and sustain public confidence.