Herpes Simplex Virus Keratitis Reactivation after SARS-CoV-2 BNT162b2 mRNA Vaccination: A Report of Two Cases

Ocul Immunol Inflamm. 2021 Aug 18;29(6):1238-1240. doi: 10.1080/09273948.2021.1986548. Epub 2021 Oct 12.


Purpose: To report two cases of herpes simplex virus keratitis reactivation following Pfizer-BioNTech COVID-19 (BNT162b2) mRNA vaccination.

Methods: Two patients (one male, age 42 years, and one female, age 29 years) who are known to have herpetic keratitis presented to our emergency room in a time frame between 4 days and 4 weeks of receiving the vaccine. One patient presented with necrotizing stromal keratitis; the other presented with endotheliitis and epithelial keratitis. PCR for herpes simplex virus (HSV) was obtained from the two patients, and all cases received systemic acyclovir.

Results: PCR for HSV came positive in both cases. Patients responded well to the provided treatment.

Conclusion: Ocular herpetic infection may be activated by COVID-19 (BNT162b2) mRNA vaccine. Treating physician should be alert to such associations, and patients should be followed closely. No direct causality has been proven, but further reporting and investigating similar conditions is recommended.

Keywords: Herpes simplex; Pfizer-bioNTech vaccine; keratitis; mRNA vaccine.

Publication types

  • Case Reports

MeSH terms

  • Acyclovir / therapeutic use
  • Adult
  • Antiviral Agents / therapeutic use
  • BNT162 Vaccine / adverse effects*
  • COVID-19 / prevention & control*
  • Female
  • Herpesvirus 1, Human / genetics
  • Humans
  • Keratitis, Herpetic / diagnosis
  • Keratitis, Herpetic / drug therapy
  • Keratitis, Herpetic / etiology*
  • Latent Infection / diagnosis
  • Latent Infection / drug therapy
  • Latent Infection / etiology*
  • Male
  • Polymerase Chain Reaction
  • SARS-CoV-2*
  • Vaccination / adverse effects*


  • Antiviral Agents
  • BNT162 Vaccine
  • Acyclovir