This condition subsides without any permanent complication. But in some severe cases, this condition damages the cornea by scarring. If this should occur, the patient is faced with a permanent vision loss. It is very important that this condition is treated immediately with anti-viral eye drops or ointment to prevent corneal scarring. One to two out of one thousand people will have at least one episode of active herpes simplex eye infection. People who are aged thirty to forty are at high risk of developing this condition.
Herpes simplex eye infection happens when the cornea becomes infected. The cornea is the clear cover of the eyes. Keratitis or the infection of the cornea can also cause herpes simplex infection. The infection of the cornea can happen in the upper layer of the cornea. This condition is called epithelial keratitis. If the infection affects the inner layer of the cornea, this is called the stromal keratitis. This is a lot more serious and is highly likely to cause corneal scarring.
Aside from the cornea, other eye parts can also be affected. The conjunctiva can also have mild to temporary inflammation or conjunctivitis. The eyelids can also be inflamed or the condition called blepharitis.
Once the cornea is infected, the inner, deeper parts of the eyes like the iris and the retina will also be infected.
Types of Herpes Simplex infections
There are basically two types of herpes simplex virus. The type 1 virus causes the common cold sores in the mouth and the herpes simplex of the eyes. The type 2 virus causes the genital herpes. This strain rarely causes the cold sores in the mouth and eye infections.
- Type 1 herpes simplex infections. Primary infection occurs the first time a person is infected by it. Most of the patients get infected by this virus during childhood and can be passed on through moist skin of the mouth. It can also be passed on through contact like kissing someone with cold sore. Most people who are infected with primary infection will not have any symptoms but some will have them. Once infected, the virus stays in the patient’s body. It stays inside as an inactive or dormant form in the root of the facial nerve known as the trigeminal nerve.
- Most people will have the virus as an inactive or dormant form. This will cause no further problem.
- Some people will have the virus in the activated form and once this happens it will multiply. The virus particles will then travel down the nerve and cause episodes of active infection:
- The virus can also travel down the nerve to the mouth. This causes cold core.
- The virus can also travel down the nerve to the eye to cause active eye infection.
Symptoms of Active Infection
Most of the active infection case is because of re-activation of the viral strain. This can happen at a later period from when the person has occurred primary infection. The symptoms would include the following:
- Pain or ache in the eyes.
- Photophobia or the discomfort when bright light hits the eyes.
- Eyes have become red around the cornea.
- Eyes become watery.
- Vision is blurred or reduced.
The doctor examines the eyes using a magnifier. The doctor could also put stain or dye in the eye to show any anomaly in the corneal shape. If the patient has herpes simplex infection, the doctor will see small ulcerations in the cornea or dendritic ulcer. Dendritic is ‘many fingered’. The ulcerations are not round but they have a smooth edge with many branches – thus dendritic because they resemble fingers.
If the eye specialist or the doctor suspects that the patient has herpes eye infection, the eye specialist will perform a more detailed magnification test of the eyes. This is done to assure the right diagnosis and to known is the eye infection is in the upper layer of the cornea or in the deeper parts of the eye.
Treatment for Herpes Simplex Eye Infection
- Epithelial keratitis. This is treated using anti-viral eye drops or ointments like the products acyclovir and ganciclovir. These products cannot kill the virus but it can stop them from multiplying. The products should be used for weeks to see the results. These drugs aim to protect the cornea from damage. The eye specialist or the doctor can scrape the infected part of the cornea to remove the affected cells.
- Stromal keratitis. The treatment for this condition is the same for epithelial keratitis but in addition to using anti-viral eye drops and ointments, the eye specialist can also add steroid eye drops to reduce inflammation. But caution should be advised when using steroid eye drops since this may cause bad side effects for the patient. Anti-viral tablets can also be used.
- Eyelids or conjunctiva are affected. There are no treatments or intervention needed for this type. The infection can subside naturally within one to three weeks. The patient is advised to go to regular eye check=up to insure that the cornea is not damaged in any way.
Prevention of Recurring Infections
Most of the patients will have recurring active infection. This is caused by the re-activation of the virus. People who have active infection will have recurrence within ten years. In one out of ten cases, the recurrence can happen quickly within one year.
If the patient notices that the recurrences occur too frequently or severely, then the eye specialist can advise the patient to take anti-viral tablets every day to prevent further events of active infection. Anti-viral tablets can lower the recurrence down to fifty percent.
Active infection can also be triggered by exposure to sunlight. The patient should always remember to wear sunglasses to prevent recurring active infection from happening. It is also advisable that the patient stay indoors to keep the activation minimal.
Prognosis for Herpes Simplex Eye Infection
The occurrence of keratitis causes great alarm because it scars the cornea. Once scarring occurs, the patient’s vision will be affected. The scarred cornea will also appear as frosted glass as it becomes transparent:
- Epithelial keratitis subsides in one to two weeks. This condition does not cause any serious scarring.
- Stromal keratitis can cause loss of vision and scarring of the cornea.
- Recurring events of active infection will only make the existing scars in the cornea worse.
- Immediate treatment should be done with anti-viral eye drops or tablets to reduce damage during every infection episode.
Nine out of ten patients can maintain a good vision. They are able to drive. In severe cases of recurring herpes simplex eye infection, it can cause impaired vision; serious scarring and can also cause blindness. Once blindness occurs, a corneal transplant should be done to restore vision.