Safety of COVID-19 vaccination among patients with history of allergic reactions

Introduction:
Vaccination is considered the most effective method of preventing diseases and their complications. Unfortunately, many people question their legitimacy and safety. At the beginning of 2021, a few months after the announcement of the SARS-CoV-2 pandemic by the World Health Organization (WHO), the first COVID-19 vaccines were granted a conditional marketing authorization. mRNA vaccines have attracted great interest due to the use of new technology and the content of polyethylene glycol (PEG 2000) in their composition, which may induce anaphylaxis. Due to vaccine tolerance concerns, some vaccination centres have refused to administer the vaccine to patients.

Aim:
Risk assessment of allergic reactions after administration of the COVID-19 vaccine.

Material and methods:
115 patients were admitted to the Department of Allergology and Clinical Immunology in Katowice, including 107 patients with a high risk of anaphylaxis after vaccination according to the referring physician and 8 patients with a history of hypersensitivity reactions after the first dose of COVID-19 vaccination. Patients were referred for diagnosis of hypersensitivity to components of the Pfizer/BioNTech COVID-19 vaccine and administration of the vaccine in a hospital setting. During hospitalization, all patients underwent skin prick and intradermal tests with the Pfizer/BioNTech COVID-19 vaccine components, with negative results. Patients were administered the Pfizer/BioNTech COVID-19 vaccine intramuscularly, followed by at least 60 minutes of observation in the Department.

Results:
No symptoms of early hypersensitivity were observed. One patient developed urticarial lesions on the skin of the neck approximately 4-5 hours after vaccination.

Conclusions:
The risk of anaphylaxis after COVID-19 vaccine administration is low, and only a small group of patients with an allergic history require a specialised diagnostics. Physicians authorised to administer the vaccine should be acquainted with the latest recommendations, assess the risk of anaphylaxis and avoid unnecessary delays in administering a vaccine that can protect against severe morbidity and death.