Comparison of the post-marketing safety profile between influenza and COVID-19 vaccines: An analysis of the vaccine adverse event reporting system

The global coronavirus disease (COVID-19) epidemic can be partially managed by vaccines; however, the public must be informed about the safety of COVID-19 vaccines to avoid hesitancy. Therefore, it is important to know the safety profile of the COVID-19 vaccine by comparison to that of a well-known vaccine, such as the influenza vaccine. Hence, this retrospective descriptive study was conducted to evaluate and compare the number of adverse effects (AEs) reported to the Vaccine Adverse Event Reporting System (VAERS) for both COVID-19 and influenza vaccines, identify the most common AEs of each vaccine, and compare the frequency and outcomes of using COVID-19 and influenza vaccines in the U.S. population. Surveillance reports from 1st December 2020 to 8th October 2021 of both vaccines were retrieved from the U.S. VAERS. A total of 544,025 and 15,871 reports of post-COVID-19 and - influenza vaccine AEs were reported to the VAERS, respectively. Females reported > 58% and nearly 70% of influenza - and COVID-19 vaccine-associated AEs, respectively. The estimated incidence rates of AEs associated with COVID-19 and influenza vaccines in the U.S. were 1.36 and 0.12 per 1,000 persons, respectively. The incidence of AEs was higher among COVID-19 vaccine recipients than that among influenza vaccine recipients. COVID-19 vaccine recipients have a two-fold higher risk of mortality and life-threatening events than influenza vaccine recipients. However, most of the reported AEs were similar between the two vaccines in terms of symptoms.