Infectious epithelial keratitis is a rare, potentially sight-threatening, acquired ocular disease chracterized by corneal epithelium inflammation resulting from viral (mainly Herpes Simplex virus), bacterial, fungic or protist infection, manifesting with variable symptoms, such as conjunctival hyperemia, lacrimation, rapid onset of pain, blurred vision and/or photophobia, depending on the causative agent. The disease is infectious epithelial keratitis (MONDO_0015289, a Monarch Disease Ontology entry).