Varicella Zoster Reactivation Causing Acute Retinal Necrosis following mRNA COVID-19 Vaccination in a Young Immunocompetent Man.

Background: Varicella zoster reactivation is an increasingly recognised event following mRNA COVID-19 vaccination. In addition, various ocular inflammatory and infectious adverse events following COVID-19 vaccination have been described in the literature. This case report describes acute retinal necrosis (ARN) secondary to varicella zoster virus (VZV) reactivation following COVID-19 mRNA vaccination.
Case Description: A 42-year-old immunocompetent man developed left ARN 12 days following first dose of Pfizer BioNTech mRNA COVID-19 vaccination. Aqueous and vitreous tap polymerase chain reaction testing was positive for VZV. Good visual outcome was achieved with combination therapy, including intravitreal foscarnet, oral valaciclovir and prednisolone, topical dexamethasone and atropine, and barrier retinal laser. Second dose of the vaccine is planned under cover of high-dose oral valaciclovir therapy.
Conclusion: This case illustrates the possible association between COVID-19 vaccination and potentially blinding VZV reactivation. Therefore, prompt ophthalmic assessment is recommended in patients with visual disturbance following COVID-19 vaccination.