Ophthalmia, or eye disease.
Archimandrite Nikifor’s Biblical Encyclopedia
The prevalence of this disease in Egypt, where a large part of the population suffers from it, or goes entirely blind from it, is known to every traveler in Egypt. In Palestine, too, a considerable portion of the population is subject to eye diseases, and on the basis of biblical references we may suppose that it was likewise widespread in ancient times. The blind are frequently mentioned in the sacred books of the Old and New Testaments, and the humane measures prescribed by the Law of Moses concerning the treatment of this class of unfortunates give grounds for thinking that their number among the Hebrew people was considerable (Lev. 19:14, Deut. 27:18).