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Conjunctivitis Infection


Conjunctivitis is a common eye condition that affects the thin, transparent lining of tissue called the conjunctiva, the conjunctiva lines the inner surface of the eyelid and covers the white of the eye. Conjunctivitis infection is often referred to as red eye.

What are the symptoms of Conjunctivitis?

Conjunctivitis can be in one or both eyes, the main symptom is a red bloodshot eye. Other symptoms you may experience are as follows:

  • A itchy or burning eye.
  • Eyes that water more than usual.
  • A discharge, that might be yellow or green in colour that sticks the eyelashes together, making it difficult for you to open your eye after sleeping.
  • A gritty feeling like something being in the eye.
  • Swollen eyelids

If an allergy is the cause, both eyes will be affected and you might also have other symptoms of hay fever or asthma.  If a viral infection is the cause you may also have cold like symptoms.

Visit your doctor if your baby has red eyes. You should also seek advice if you wear contact lenses in case you are allergic to them.

You should see your doctor urgently or go to A&E if there is pain in your eye, you have a sensitivity to light, there are changes in vision as these could be the signs of  a more serious condition.

What are the causes?

Conjunctivitis can be caused by a viral infection, such as the common cold or flu, a bacterial infection, irritant or an allergy. The virus associated with the common cold is the most common cause of conjunctivitis. Occasionally a sexually transmitted disease can cause conjunctivitis, if you or a  partner have chlamydia and then you rub your eye after sexual contact it can be transferred.  If you have protected sex you are unlikely to contract it. Irritant conjunctivitis can be caused by air irritants like pollution, smoking or chlorine in swimming pools. Irritant conjunctivitis can also be caused by something rubbing against your eye like a bit of dirt, eyelash or make up. Allergies such as hay fever or the ingredients in some cosmetics can also cause conjunctivitis.

Is Conjunctivitis contagious?

If conjunctivitis is caused by an infection then yes it is very contagious. To prevent the spread ensure you wash your hands regularly and wash pillows and flannels in hot water.  Do not share your pillows, make-up or towels. However, if an allergy such as hay fever is the cause then it is not contagious.

How is the condition  diagnosed?

Most people will know they have conjunctivitis from their symptoms and does not normally require a doctor to diagnose. Conjunctivitis is usually diagnosed by looking at the eye, your doctor will ask questions about your symptoms.  The doctor may take a swab of your eye to send away to a laboratory to help identify the cause.

How is it treated?

The treatment you require will depend on the cause. If a bacterial infection is the cause then you may require antibiotic eye drops or ointment. However, if a virus or an allergy is the cause antibiotics will not help. On rare occasions if an infection is severe then anti-inflammatory steroid drops may be required. If untreated conjunctivitis will usually clear itself in a couple of weeks. If a sexual transmitted infection is the cause this might take longer to clear up.

To ease your symptoms at home, use  a cold flannel to bathe the eye or use a cold compress and relax with it on for 5-10 minutes. Gently rub your eyelashes to clean off any crusts and if you wear contact lenses avoid wearing them until your eyes are better. Speak to your pharmacist for advice. You should also avoid wearing eye make-up.

If an allergy is the cause then it is best to try to remove the irritant, however antihistamines might help ease the symptoms.

If your symptoms last more than 2 weeks then you should visit your doctor.

How can I prevent conjunctivitis?

To avoid conjunctivitis you should always wash your hands thoroughly and regularly. Try to avoid rubbing your eyes, cover your mouth and nose when coughing or sneezing. Avoid sharing items such as towels, pillows and make up. If you wear contact lenses always follow the instructions for your lenses.

Are there any long term effects from this condition?

It is very rare for conjunctivitis to cause any long term damage to the eye or vision, however, the infection can spread to the cornea and cause scarring which could cause problems with vision.