6 Patients with Autoimmune Inflammatory Disorders Develop Shingles After mRNA Vaccine

April 21, 2021

The Tel Aviv Medical Center and Carmel Medical Center are conducting a study monitoring adverse events in patients with autoimmune inflammatory disorders. This includes patients with rheumatoid arthritis, vasculitis, myositis, Sjogren’s, and spondyloarthritis for 6-weeks post-COVID-19 vaccination. Of 491 patients with autoimmune inflammatory rheumatic diseases, six have been diagnosed with herpes zoster (shingles) for the first time after receiving an mRNA vaccine. Five cases occurred after receiving the first dose, and one after the second dose. Five of the six patients had not been vaccinated for shingles prior to receiving the COVID-19 vaccine. 
As of now, there have not been reports of shingles in clinical trials. That being said, there is limited data regarding the safety of COVID-19 vaccines in those with autoimmune and rheumatic disease, as immunocompromised participants were not included in clinical trials.

The authors of this study make it clear that these six cases do not determine a causal link, especially since other factors were likely to impact these outcomes. For example, the risk of shingles doubles in patients with rheumatoid arthritis. Risk also increases when taking high doses of prednisone, and doubles when being treated with certain anti-rheumatic drugs (such as tofacitinib, e.g. Xeljanz). “Potential mechanisms that might explain the pathogenetic link between mRNA-COVID-19 vaccination and herpes zoster reactivation are related to stimulation of innate immunity through toll-like receptors by mRNA-based vaccines” (1).  Five patients received antiviral treatments which resolved their shingles; the five patients who had only received one dose before the onset of their symptoms received the second dose and did not experience other adverse effects.

Herpes zoster reactivation after vaccination has been studied with other diseases such as Hepatitis A and rabies (2). According to the authors of this study, these are the first reported cases of shingles reactivation after a COVID-19 vaccine. There has also been an uptick of shingles cases reported globally in the context of COVID-19 infection (1). Further investigation and reporting of adverse events is crucial to understanding the prevalence of herpes zoster reactivation after COVID-19 infection. This study started in December 2020 and is ongoing.