The total duration of the rash is approximately 6 days. Ocular manifestation Conjunctivitis, along with cough and coryza, is considered as a classical triad in measles. However, it is not always present. The conjunctivitis is usually mild, catarrhal, papillary and nonpurulent. Pseudomembranes may occur, and in debilitated patients, severe, true conjunctival membranes may develop.
Epithelial keratitis is even more common than conjunctivitis.
It is usually mild and present in both eyes of all infected patients. The keratitis develops in the prodromal phase or at the time of the onset of the skin rash and resolves without scarring several days afterwards. In some patients it may persist as long as 4 months. Retinitis is, compared to keratitis and conjunctivitis, rarely present. It was described as macular edema, neuroretinitis, macular star formation, the presence of attenuated arterioles, and disc edema.