Safety Surveillance for Hepatitis A Vaccine using the U.S. Vaccine Adverse Event Reporting System (VAERS) database

Hepatitis A virus (HAV) infection remains a significant global public health concern. Vaccination is the key to preventing HAV, and its efficacy has been confirmed. While most reported adverse events following hepatitis A vaccination are mild, recent years have seen limited research on its safety based on real-world pharmacovigilance analysis. We collected all the reports in the VAERS database from 1995 to 2024 related to the Hepatitis A Vaccines, and the incidence of HAV infection from GBD 2021. A disproportionality analysis using the reporting odds ratio (ROR) with a 95% confidence interval was performed. 45,645 individual case safety reports referring to Hepatitis A Vaccine have been recorded in VAERS until 2024, which corresponds to 151,800 drug-reaction pairs. The most frequently reported were non-serious: pyrexia (5,951 reports), Injection Site Erythema (5,071), etc. Pallor, injection site induration, injection site erythema, and so on, show a statistically significant ROR. There are some differences between the studied detected signals and the package insert information. The analysis of adverse event signals based on the VAERS database provides relatively reliable results. It is recommended that vaccine manufacturers further evaluate these newly identified signals and update the package inserts accordingly. Additionally, enhanced monitoring of adverse events during vaccine administration is necessary.