Herpes keratitis is a viral infection of the eye caused by the herpes simplex virus (HSV). There are two main types of the virus. Type I is the most common and the reason for the common cold sores. Type II is a sexually transmitted herpes virus.
Type I and type II can cause an infection to the eye, but type I is the most frequent offender. The infection can transfer to the eye even by only touching it.
Type I herpes virus is very contagious and often transmitted by contact with the skin of someone who has this virus.
If herpes simplex affects the eyes, it usually infects the eyelids, conjunctiva and cornea. It can also infect the inner part of the eyes, but this is very rare. Around 90% of the population has herpes type I, usually in childhood.
The treatment of herpes keratitis depends on its severity. Light infections are usually treated with antiviral medications. Severe cases can cause loss of vision and corneal transplantation.