Herpes simplex eye infections are a potentially serious type of eye infection.
They're caused by a virus called herpes simplex – usually the herpes simplex virus type 1 (HSV-1), which also causes cold sores.
It's important to get medical help if you think you may have the infection, as your vision could be at risk if it's not treated.
Symptoms of a herpes simplex eye infection can include:
Usually only 1 eye is affected.
Get medical help as soon as possible if you have these symptoms. They could be caused by a herpes simplex infection or another eye condition that needs to be treated quickly.
If it's not treated, there's a chance your vision could be affected.
You can get help and advice from:
If you wear contact lenses, take them out and do not use them again until you're advised by a medical professional that it is safe to do so.
Most herpes simplex eye infections get better in 1 to 2 weeks, although they can last longer. Treatment is usually needed to reduce the risk of complications.
The main treatments are:
Make sure you follow the advice you're given and take any prescribed treatment as directed. It's important to complete the recommended course of any medicine even if your symptoms go away. This will help stop the virus coming back.
Herpes simplex eye infections usually occur when a previous infection with the virus reactivates and spreads to the eye.
Nearly everyone is exposed to the herpes simplex virus during childhood. Most people will not notice this because there are often no symptoms. But afterwards the virus will remain inactive in the body.
In some people, the virus can be reactivated later on. This can happen randomly or may be triggered by:
Herpes simplex eye infections do not usually cause further problems if they're treated promptly, but about 1 in 4 cases are more serious and carry a higher risk of complications.
These can include:
It's also likely the infection will return at some point. Most people will experience more than 1 infection, with about 1 in 5 having a recurrence within a year.