Possible Triggering Effect of COVID - 19 Vaccination in Psoriasis Patients -An Essential Review

Psoriasis is an inflammatory skin condition characterized by a chronic relapsing course that is able to impact negatively a patient's quality of life. Diverse triggering factors can lead to psoriasis exacerbation, including vaccination, as the most common vaccine associated with psoriasis exacerbation is the vaccine against influenza. Psoriasis exacerbation has also been reported after the Pfizer and Corona Vac vaccine. Nowadays, the world scientific community agrees that vaccine is the most promising weapon against the COVID-19 infection and severity. Despite the fact that 272 vaccines against SARS-CoV-2 virus are in progress, only four of these, have been approved and subsequently distributed worldwide for use, are based on innovative procedures and are quite different from each other in terms of composition. Clinical professionals, such as dermatologists may be unfamiliar with the effects of those vaccines, however, there is the strong need for them to understand the critical role of vaccines, with a focus on the necessity to vaccinate individuals suffering from immune-mediated skin diseases, such as psoriasis. Psoriasis patients have shown morphologic alterations from chronic plaque-type to guttate psoriasis after their vaccination, however, the exact mechanism of psoriasis exacerbation remains unclear. It is possible that Th17 cells induced by COVID-19 vaccines may play a critical role. In the current pandemic situation, psoriasis patients who do not have contraindications to vaccination should benefit from COVID-19 vaccines in the prevention of severe COVID-19 infection and fatality. The present review presents the possible implication of COVID-19 vaccination in psoriasis patients.