Cutaneous reactions to COVID-19 vaccines: A review.

Background: The increasing number of reports on cutaneous reactions following COVID-19 vaccination has led to growing concerns among certain groups. Objective: We reviewed the published reports of cutaneous lesions after COVID-19 vaccination. Methods: We conducted a literature search for original and review articles published between January 1, 2020, and September 27, 2021. Results: Eleven cutaneous reactions associated with COVID-19 vaccines were determined; the most prevalent reactions were local injection site reactions, delayed local reactions, urticaria, angioedema, and morbilliform eruptions. There were more reports on skin reactions following the administration of messenger RNA-based vaccines than on those following the administration of adenoviral vector or inactivated whole-virus vaccines, in part, due to their higher administration rate. Most reported skin reactions occurred after the first vaccine dose. Limitations: A reporting bias could not be excluded, and skin biopsy results were not available for most included individuals. Moreover, given that the included trials focused on vaccine efficacy, there was a lack of details concerning cutaneous reactions and participant information. Conclusion: Not all cutaneous reactions observed after COVID-19 vaccination are hypersensitivity reactions. Different cutaneous reactions may reflect underlying immune responses to the vaccines. A large majority of COVID-19 vaccination reactions were mild and self-limiting, and people should be encouraged to complete their vaccination regimen.