Varicella zoster virus infection due to Pfizer-BioNTech mRNA COVID-19 vaccine and sinovac vaccine in two relapsing-remitting multiple sclerosis patients during fingolimod therapy

Along with the Covid-19 infection, newly developed Covid-19 vaccines have also entered our lives. While the immunomodulatory/immune suppressor treatments are used mainly in individuals with diseases affecting the immune system like multiple sclerosis, possible side effects that may develop due to the vaccines applied have begun to be followed closely. Varicella-zoster virüs (VZV) reactivation also seems to be one of the complications after various Covid-19 vaccines. Here, we presented two patients who developed HZ infection after being vaccinated with two different vaccines (Pfizer-BioNTech mRNA COVID-19 and Sinovac) and thought to be related to the possible vaccine.