Polyserositis (pericarditis and bilateral pleural effusion) after COVID-19 mRNA vaccine

The coronavirus disease 2019 (COVID-19) pandemic has been responsible for more than 5.5 million deaths worldwide. Vaccination is the most effective method of preventing this type of disease. The efficacy and safety of COVID-19 vaccines authorized in the European Union have been assessed in clinical trials that recruited many participants. As the number of vaccinated people increases, infrequent adverse effects are expected. We would like to report a case of polyserositis (pericarditis, and bilateral pleural effusion) observed a few days after administering the Pfizer BioNTech COVID-19 mRNA vaccine (Comirnaty ® ) in a 65-year-old man with no cardiovascular, metabolic or autoimmune disorders in his history. The incidence of myocarditis and pericarditis after COVID-19 mRNA vaccines is very low (combined reports from the USA and EU suggest the incidence of 1.02 × 10 –5 and 7.61 × 10 –6 respectively). Therefore, it is vital to inform people vol-unteering for vaccination to be aware of such symptoms as chest pain, breathlessness, or irregular forceful heartbeat. Moreover, the presence of these symptoms should alert healthcare professionals to the potential risk of pericarditis associated with the administration of the COVID-19 vaccine.