Herpes zoster following inactivated COVID-19 vaccine: a coexistence or coincidence?

Abstract

Coronavirus disease (COVID-19) is a newly emerged multisystemic disease which may present with a wide spectrum of cutaneous manifestations.1 Some associated cutaneous findings are described as widespread urticaria, erythematous rash, and chicken pox-like lesions.1 In attempt to prevent both COVID-19 and viral transmission, DNA-based/RNA-based vaccines, non-replicating viral vector vaccines, and inactivated vaccines have been developed recently.2 The inactivated COVID-19 vaccines are authorized for use in some countries including Turkey which started vaccination program in January 2021. Most commonly reported adverse effects of the inactivated vaccines are injection site pain, fever, headache, nausea, vomiting, etc.3 Herein, we report an extraordinary case of varicella zoster virus (VZV) reactivation in a patient who was vaccinated against COVID-19. A 78-year-old man with a history of coronary artery disease, cerebrovascular accident, hypertension, chronic pulmonary obstructive disease, radical cystectomy, and prostatectomy performed seven years ago for bladder cancer was consulted to us for erythematous, painful, and pruritic lesions on his chest. Currently, the patient was not on any immunosuppressive therapy and the bladder cancer was cured after surgery. He reported that five days after the application of inactivated COVID-19 vaccine, some stinging and painful pimple-like lesions had appeared involving the left mammary region. No other symptoms such as fever, dyspnea, or cough were accompanied. Dermatological examination showed some crusted, hemorrhagic vesicles upon an erythematous base occupying an area corresponding to T3-T4 dermatomes (Figure 1). Our final diagnosis was herpes zoster, and we started on oral valacyclovir thrice a day for one week. He did not mention any factor that would contribute to the development of herpes zoster such as immunosuppressive drug use, radiation therapy, physical trauma, or psychological stress. Varicella zoster virus (VZV) remains latent in dorsal-root or cranial-nerve ganglia after primary infection. Herpes zoster caused by reactivation of VZV may occur spontaneously or be triggered by trauma, stress, fever, or immunosuppression. Recently, VZV reactivation in immunocompetent cases during COVID-19 infection has also been reported,4-6 which is suggested to develop as a result of COVID-19-induced lymphopenia and functional impairment of CD4+ T cells.7, 8 The median time between COVID-19 diagnosis to development of herpes zoster was reported as 5.5 days.6 Similarly, the reactivation appeared 5 days after COVID-19 vaccination in our case. Additionally, Walter et al9 reported three different cases of herpes virus reactivation following inactivated influenza, hepatitis A, and rabies with Japanese encephalitis vaccines. It is considered that vaccine-related immunomodulation including suppression of cellular immunity by live attenuated vaccines and attenuated alloreactivity caused by inactivated hepatitis B vaccine may be responsible for the reactivation of herpes virus infections.9, 10 To our knowledge, this is the first case of VZV reactivation following COVID-19 vaccination. Even though it is not possible to establish a straightforward relationship between herpes zoster and inactivated COVID-19 vaccine, immune dysregulation created by the vaccine may play a role in the reactivation of latent VZV infection in the current case. COVID-19 pandemic seems to be a favorable period for large-scale epidemiological studies to elucidate the relationship between the vaccination and herpes zoster reactivation due to planned massive vaccination. We declare that there is no conflict of interest of all authors in this work. No financial support was provided for the conduct, preparation, collection, analysis, interpretation, and writing of the report. Informed consent and permission for publication of medical images were obtained from the patient.