COVID-19 mRNA Vaccines: A Retrospective Observational Pharmacovigilance Study.

ABSTRACT

BACKGROUND AND OBJECTIVE: Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus has caused millions of deaths worldwide. The mRNA vaccines prevented the figure from being more severe. The objective of this retrospective study is to evaluate the safety of COVID-19 vaccines by analyzing the adverse events following immunization (AEFIs). METHODS: A retrospective observational pharmacovigilance study was conducted, based on the collection of reports of suspected AEFIs reported between 1 January 2021 and 31 December 2021 at the Naples 3 local health authority. AEFIs were stratified and described according to mRNA vaccine, demographics, clinical status, description of AEFI, and degree of severity. In 2021, local health authority Asl Naples 3 South received 1164 reports of suspected adverse events that occurred following the administration of mRNA vaccines. RESULTS: During the reporting period, 746 reports were related to the Comirnaty vaccine (64.1%), 281 to the Vaxzevria vaccine (24.1%), 107 to the Spikevax vaccine (9.2%), and 30 to the Jcovden vaccine (2.6%); 89.3% of the reports were classified as not serious (N = 1039 reports), the remaining 10.7% as serious (N = 125 reports). CONCLUSIONS: This retrospective pharmacovigilance study demonstrates that COVID-19 mRNA vaccines are safe in all population groups.

Pharmacovigilance is an activity that ensures the safety of health care treatments. The COVID-19 pandemic has accelerated the administration of vaccines whose efficacy and safety is to be evaluated. In the year 2021, an analysis of all reported adverse events following immunization (AEFIs) to the vaccine was conducted on a sample of about 1 million people with the aim of understanding efficacy and safety. All adverse events were divided by age, sex, type of reaction, and severity. Serious reactions were divided into subcategories to report the most common critical issues. At the conclusion of the work, it can be seen that COVID-19 mRNA vaccines are safe but can give serious cardiovascular (12% of the total number of serious reports) and neurological (one serious case that led to the development of Guillain Barré syndrome) side effects that need to be monitored by medical personnel.