Historical observations on herpetic keratitis.

The history of herpetic keratitis is presented. The similarities and differences between dendritic keratitis and herpes labialis are enumerated, with the suggestion that the similarities (in onset, pathology, and clinical course) far outweigh the differences. The principal difference seems to be that the avascalarity of the cornea retards the immunologic responses. Important points in the history of herpetic keratitis include (1) the close association of herpetic disease with malaria around the turn of the century; (2) the relatively benign nature of the disease, in contrast to herpes zoster keratitis; (3) the unfavorable response of the disease to immunosuppressive measures and diseases; (4) the failure of chemotherapy to influence favorably the natural history of the disease; and (5) the increasing visual damage caused by the disease since 1952 when corticosteroids were introduced into ocular therapy. Mention is made of the increasing problem of venereal herpes, with resultant neonatal herpetic keratitis, retinitis, and encephalitis.