Reactivation or recurrence of adenovirus keratitis; Reactivation or recurrence of adenovirus keratitis; This literature-non-study case was reported in a literature article and describes the occurrence of KERATITIS VIRAL (Reactivation or recurrence of adenovirus keratitis) and ADENOVIRUS REACTIVATION (Reactivation or recurrence of adenovirus keratitis) in a 30-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.   LITERATURE REFERENCE:     The patient's past medical history included Epidemic keratoconjunctivitis (history of epidemic keratoconjunctivitis secondary to adenovirus 2 months earlier).   On 10-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 10-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 17-Jan-2021, the patient experienced KERATITIS VIRAL (Reactivation or recurrence of adenovirus keratitis) (seriousness criterion medically significant) and ADENOVIRUS REACTIVATION (Reactivation or recurrence of adenovirus keratitis) (seriousness criterion medically significant). The patient was treated with DEXAMETHASONE, TOBRAMYCIN (TOBRAMYCIN/DEXAMETHASONE) (ophthalmic) in 2021 for Keratitis viral, at an unspecified dose and frequency. At the time of the report, KERATITIS VIRAL (Reactivation or recurrence of adenovirus keratitis) and ADENOVIRUS REACTIVATION (Reactivation or recurrence of adenovirus keratitis) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Slit-lamp examination: revealed inferior subepithelial infiltrates of the right eye and diffuse subepithelial infiltrates of the left and resolution of exam findings.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered KERATITIS VIRAL (Reactivation or recurrence of adenovirus keratitis) and ADENOVIRUS REACTIVATION (Reactivation or recurrence of adenovirus keratitis) to have an unknown relationship.    No concomitant medications were reported.  The observational case series concerns nine patients who received COVID-19 vaccinations from January to June of 2021 who presented with symptoms of keratitis within 14 days. The patient in question had a history of epidemic keratoconjunctivitis secondary to adenovirus 2 months earlier. She presented with a reports of photophobia and decreased vision in the left eye. The patient received first COVID-19 vaccine 1 week prior to the onset of her new symptoms. Slit-lamp examination of the cornea revealed inferior subepithelial infiltrates of the right eye and diffuse subepithelial infiltrates of the left. The patient was started on tobramycin/dexamethasone in both eyes with resolution of her symptoms and exam findings.  The authors stated that immunological reaction following mRNA-based COVID-19 vaccinations may trigger new-onset or reactivation of keratitis. In addition, since the intense immunological reaction following COVID-19 vaccination increases levels of the cytokines, the authors hypothesized that it may trigger or reactivate a keratitis infection in these patients. Although more patients reported symptoms after their first dose, a faster onset was observed after patients received their second dose (10.5 days vs 4.4 days, respectively). This observation could be explained by the 30-fold stronger immune response following the second vaccine dose. Author stated that it was crucial to note that it have made only temporal associations, and causality cannot be determined. It was believed that  that the immunological response following COVID-19 vaccination may explain that phenomenon, though causality cannot be proven.  Company comment:This literature-non-study case report concerns a 30-year-old female patient with medical history of epidemic keratoconjunctivitis secondary to adenovirus 2 months earlier, who experienced serious (medically significant) unexpected events of Keratitis viral (adenovirus keratitis) and Adenovirus reactivation. Reportedly, 7 days after the patient had received the first dose of the mRNA-1273 vaccine, the patient presented with reports of photophobia and decreased vision in the left eye. Slit-lamp examination of the cornea revealed inferior subepithelial infiltrates of the right eye and diffuse subepithelial infiltrates of the left. The patient was treated with tobramycin/dexamethasone in both eyes with resolution of her symptoms and exam findings. The authors concluded that immunological reaction following vaccination might trigger reactivation of adenoviral keratitis in this patient, having in mind medical history of previous epidemic keratoconjunctivitis. Therefore, previous medical history of epidemic keratoconjunctivitis remains a confounder. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.   This case was linked to US-MODERNATX, INC.-MOD-2022-674525, US-MODERNATX, INC.-MOD-2022-674614, US-MODERNATX, INC.-MOD-2022-674615 (Linked Report).; Sender's Comments: This literature-non-study case report concerns a 30-year-old female patient with medical history of epidemic keratoconjunctivitis secondary to adenovirus 2 months earlier, who experienced serious (medically significant) unexpected events of Keratitis viral (adenovirus keratitis) and Adenovirus reactivation. Reportedly, 7 days after the patient had received the first dose of the mRNA-1273 vaccine, the patient presented with reports of photophobia and decreased vision in the left eye. Slit-lamp examination of the cornea revealed inferior subepithelial infiltrates of the right eye and diffuse subepithelial infiltrates of the left. The patient was treated with tobramycin/dexamethasone in both eyes with resolution of her symptoms and exam findings. The authors concluded that immunological reaction following vaccination might trigger reactivation of adenoviral keratitis in this patient, having in mind medical history of previous epidemic keratoconjunctivitis. Therefore, previous medical history of epidemic keratoconjunctivitis remains a confounder. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. US-MODERNATX, INC.-MOD-2022-674525:73 YO male US-MODERNATX, INC.-MOD-2022-674614:84 YO female US-MODERNATX, INC.-MOD-2022-674615:54 YO female