This literature-non-study case was reported in a literature article and describes the occurrence of KERATITIS (Keratitis) in an 84-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis.   LITERATURE REFERENCE.     Family history included Herpes simplex (her daughter had active herpes.).   On 01-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 29-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 01-Apr-2021,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced KERATITIS (Keratitis) (seriousness criterion medically significant). The patient was treated with VALACYCLOVIR [VALACICLOVIR] (oral) in 2021 at a dose of 1 gram twice a day; GANCICLOVIR in 2021 at a dose of 5 times a day; OFLOXACIN in 2021 at a dose of UNK UNK, qid and PREDNISONE (oral) in 2021 at an unspecified dose and frequency. In 2021, KERATITIS (Keratitis) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In 2021, Slit-lamp examination: revealed limbal curvilinear epithelial defects, diffuse keratic precipitates, inferotemporal edema, and 20 percent thinning of her temporal cornea. examination was also significant for 2 plus anterior chamber reaction..     For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   The patient had no significant past ocular history and denied any history of oral ulcers or herpes simplex virus. No concomitant medications were provided. The patient was referred for evaluation secondary to 7 weeks of decreased vision, photophobia, and injection of left eye. Within next month, the patient demonstrated significant improvement with the resolution of the infiltrate, epithelial defect, and uveitis. The patient was returned to baseline.  Patient initially received valacyclovir, ganciclovir, ofloxacin as well as topical lubrication and prednisone was added to treatment regimen a week later. The author reported that new-onset keratitis in temporal proximity to the COVID-19 vaccinations and believed that the immunological response following COVID-19 vaccination may explain this phenomenon, though causality cannot be proven. As untreated keratitis can cause severe symptoms, including complete loss of vision, documentation and discussion of such cases as they occur is critical to ensure timely treatment. Author hypothesized that the intense immunological reaction following COVID-19 vaccination increases levels of cytokines, which may had triggered or reactivated a keratitis infection. Also, more patients reported symptoms after their first dose, a faster onset was observed after patients received their second dose.    This case was linked to US-MODERNATX, INC.-MOD-2022-674613, US-MODERNATX, INC.-MOD-2022-674525, US-MODERNATX, INC.-MOD-2022-674615 (E2B Linked Report).  This literature-non-study case, concerns a 84-year-old female patient with no past ocular history, oral ulcers or herpes simplex virus infection, though her daughter had active herpes reported, who experienced the unexpected serious (medically significant) event of Keratitis about three days after second dose of mRNA-1273 vaccine in the covid 19 vaccination series. Patient was referred for evaluation secondary to 7 weeks of decreased vision, photophobia, and infection of her left eye. Slit-lamp examination of the cornea revealed limbal curvilinear epithelial defects, diffuse keratic precipitates, inferotemporal edema and 20% thinning of her temporal cornea. Her examination was also significant for 2+ anterior chamber reaction. She was prescribed valacyclovir 1 g orally twice a day, ganciclovir five times a day, ofloxacin four times a day as well as topical lubrication. Oral prednisone was added a week later. Over the next month, the patient demonstrated significant improvement with the resolution of her infiltrate, epithelial defect, and uveitis. Patient has returned to baseline. The family history of her daughter had active herpes could be confounder to the event. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report.; Sender's Comments: This literature-non-study case, concerns a 84-year-old female patient with no past ocular history, oral ulcers or herpes simplex virus infection, though her daughter had active herpes reported, who experienced the unexpected serious (medically significant) event of Keratitis about three days after second dose of mRNA-1273 vaccine in the covid 19 vaccination series. Patient was referred for evaluation secondary to 7 weeks of decreased vision, photophobia, and infection of her left eye. Slit-lamp examination of the cornea revealed limbal curvilinear epithelial defects, diffuse keratic precipitates, inferotemporal edema and 20% thinning of her temporal cornea. Her examination was also significant for 2+ anterior chamber reaction. She was prescribed valacyclovir 1 g orally twice a day, ganciclovir five times a day, ofloxacin four times a day as well as topical lubrication. Oral prednisone was added a week later. Over the next month, the patient demonstrated significant improvement with the resolution of her infiltrate, epithelial defect, and uveitis. Patient has returned to baseline. The family history of her daughter had active herpes could be confounder to the event. The benefit-risk relationship of mRNA-1273 Vaccine is not affected by this report. US-MODERNATX, INC.-MOD-2022-674613:30 YO female US-MODERNATX, INC.-MOD-2022-674525:73 YO male US-MODERNATX, INC.-MOD-2022-674615:54 YO female