Conjunctivitis, infective

Page last reviewed: 13/07/2011

Conjunctivitis is inflammation (swelling) of the conjunctiva. The conjunctiva is the transparent membrane (thin layer of cells) that covers the white part of the eyeball and the inner surfaces of the eyelids.

There are three types of conjunctivitis, each with a different cause. These are:

  • irritant conjunctivitis
  • allergic conjunctivitis
  • infective conjunctivitis

Irritant conjunctivitis

Irritant conjunctivitis occurs when an irritant, such as chlorine (a chemical often used to purify water) or an eyelash, gets into the eyes, making them sore. Do not rub the eyes as this can make the condition worse. The conjunctivitis should settle once the irritant is removed. If the eyes are very red and painful, seek medical attention immediately.

Allergic conjunctivitis

Allergic conjunctivitis occurs when the eyes come into contact with an allergen. An allergen is a substance that makes the immune system (the body's defence system) react abnormally, causing irritation and inflammation. For more information on this type of conjunctivitis.

Infective conjunctivitis

Infective conjunctivitis is caused by a virus, bacteria or a sexually transmitted infection (STI), such as chlamydia or gonorrhoea. The most common symptoms include:

  • reddening and watering of the eyes
  • a sticky coating on the eyelashes, particularly when waking up in the morning

How common is infective conjunctivitis?

Infective conjunctivitis is very common and is responsible for 35% of all eye-related problems recorded in GP surgeries. There are 13-14 cases for every 1,000 people every year.

Infective conjunctivitis is most common in children and the elderly. This may be because children come into contact with more infections at school. Elderly people may be more prone to infections as their immune system (the body's defence system) may be weaker.  

Outlook

Infective conjunctivitis rarely requires medical treatment. If the infection is not caused by an STI, it will normally heal by itself within one or two weeks.

If the infective conjunctivitis is caused by an STI, the condition may last several months, rather than weeks. The STI may also require separate treatment.

For most people, the condition does not cause any complications. However, newborn babies (up to 28 days old) are at risk of a more serious infection. In severe cases, this could permanently damage the eyes.

Glossary

Allergen
An allergen is a substance that reacts with the body's immune system and causes an allergic reaction.

Immune system
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and others are good for you.

Page last reviewed: 13/07/2011

The symptoms of infective conjunctivitis normally begin in one eye. After one to two days, the other eye often becomes affected too, although the first eye may be slightly worse.

The symptoms of infective conjunctivitis can vary from person to person, but may include:

  • Red eyes: this happens as a result of the irritation and widening of the tiny blood vessels in the conjunctiva (the thin layer of cells inside the eyelids and over the white part of the eyes).
  • Watering eyes: the conjunctiva contains thousands of cells that produce mucus and tiny glands that produce tears. Irritation causes the glands to become overactive, so that they water more than usual.
  • Sticky coating on the eyelashes: you are more likely to notice this when you first wake in the morning. Your eyelids may feel like they are stuck together because the mucus and pus that is produced by the infection forms into sticky clumps on your lashes.
  • Slight soreness: this usually feels like burning or as if there is grit in your eyes.
  • Enlarged lymph node in front of the ear: a lymph node is a small gland that is part of the immune system (the body's defence system). It helps protect the body from infection and may feel like a raised bump underneath the skin.

If you have infective conjunctivitis, you may also have the symptoms of an upper respiratory tract infection. An upper respiratory tract infection is an infection that affects your throat, mouth or nose. Symptoms may include:

  • coughing
  • a high temperature (fever) of 38C (100.4F)
  • sore throat
  • headache
  • aching limbs

Neonatal conjunctivitis

Many newborn babies may have what is known as a 'sticky eye'. This usually occurs when the tear duct cannot drain properly. If it cannot drain, it produces a discharge of pus, which can look similar to infective conjunctivitis. However, this condition is not serious and does not require urgent treatment.

If your baby also has redness in their eye, it may be a sign that the eye is infected and they may have infective conjunctivitis. If your baby is up to 28 days old, this could develop into a serious infection that may affect your baby's vision. 

Contact your GP straight away for advice if you think your baby may have infective conjunctivitis.

Glossary

Conjunctiva
The conjunctiva is the transparent membrane (thin layer of cells) that covers the white part of the eyeball and the inner surfaces of the eyelids.

Immune system
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Respiratory tract
The respiratory tract is a general term that is used to describe all the parts of the body that are involved in helping a person to breathe.

Unusual symptoms

Conjunctivitis can sometimes be confused with other eye conditions, such as iritis. Iritis is inflammation of the iris (the coloured part of your eye). Unusual symptoms that are not normally caused by conjunctivitis include:

  • moderate to severe pain in your eyes
  • photophobia (sensitivity to light)
  • disturbed vision
  • intense redness in one or both of your eyes

If you experience any of these symptoms, contact your GP immediately. If this is not possible, visit your nearest accident and emergency (A&E) department.

Page last reviewed: 13/07/2011

Infective conjunctivitis occurs when the conjunctiva (the thin layer of cells covering the white of your eye and the inner surface of your eyelids) becomes inflamed (swollen) as a result of an infection. The three most common causes of an infection in your eyes are:

  • bacteria, for example the strains of bacteria that more commonly cause lung and ear infections
  • a virus, most commonly an adenovirus that may also cause a sore throat and high temperature (fever) 
  • sexually transmitted infections (STIs), such as chlamydia or gonorrhoea

There are no particular signs or symptoms that will allow your GP to distinguish between a bacterial or viral cause of infective conjunctivitis. If your condition is persistent (does not heal quickly), you will have an eye swab to determine the cause of the infection

Infective conjunctivitis caused by chlamydia can be common in newborn babies. This is because, if a mother has chlamydia, the infection can be passed to the baby during birth.

Spreading the infection

You are more likely to develop infective conjunctivitis if you have been in close contact with someone who is already infected. It is, therefore, very important to wash your hands thoroughly after coming into contact with anyone who has infective conjunctivitis.

Risk factors

You may be more at risk of infective conjunctivitis if:

  • you are old or young: the condition is more common in children and the elderly, possibly because children come into contact with more infections at school and elderly people may have weaker immune systems (the body's defence system)
  • you have recently had an upper respiratory tract infection, such as a cold
  • you have diabetes (a long-term condition caused by too much glucose in the blood) or another condition that weakens your immune system (as you may be more prone to infections)
  • you are taking corticosteroids (steroids), a medication containing hormones (powerful chemicals produced by the body) that can make you more prone to infections as they weaken your immune system
  • you have blepharitis (inflammation of the rims of the eyelids), which can be caused by a bacterial infection and may lead to conjunctivitis 
  • you have been in a crowded place, such as on a crowded train (infections are easily spread in crowded places)

Glossary

Conjunctiva
The conjunctiva is the transparent membrane (thin layer of cells) that covers the white part of the eyeball and the inner surfaces of the eyelids.

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and others are good for you.

Immune system
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Respiratory tract
The respiratory tract is a general term that is used to describe all the parts of the body involved in helping a person to breathe.

Page last reviewed: 13/07/2011

In most cases of infective conjunctivitis, your GP will be able to diagnose the condition by asking about your symptoms and by examining your eyes. Red, swollen eyes that are covered in a sticky discharge are very common features of infective conjunctivitis.

Your symptoms may be confused with a different type of conjunctivitis, such as allergic or irritant conjunctivitis. These have different causes and will be treated differently. In most cases, describing how your conjunctivitis started will inform your GP of the type of conjunctivitis you have:

  • Irritant conjunctivitis is caused by an irritant, such as a chemical splashing in your eye. 
  • Allergic conjunctivitis is caused by an allergen (a substance that you are allergic too), such as pollen.
  • Infective conjunctivitis is caused by an infection, for example after being in close contact with someone else who is infected.

Swab test

In most cases of infective conjunctivitis, no further tests are necessary. However, your GP may suggest a swab test if:

  • they are unsure about the diagnosis
  • they need to determine the cause of your infection to guide your treatment
  • your conjunctivitis has not responded to treatment

A swab is a small piece of absorbent material, such as gauze or cotton, attached to the end of a stick or piece of wire. It looks similar to a small cotton bud. This is used to collect a small sample of the pus or mucus from your infected eye.

The sample will be tested in a laboratory to find out the cause of your condition. Your GP can then provide you with the most appropriate treatment.

Other conditions

If you have any unusual symptoms , such as severe pain or sensitivity to light, you may have a different eye condition. It is very important to seek medical assistance immediately, either by contacting your GP or visiting the nearest accident and emergency (A&E) department.

If you experience these symptoms, they can be a sign of a more serious condition. Your GP will need to rule out these conditions as part of your diagnosis or they may cause complications. Possible alternative conditions include:

  • Acute glaucoma: this rare form of glaucoma (an eye condition that affects your vision) causes a painful build-up of pressure in your eye.
  • Keratitis: this is when your cornea (the clear layer at the front of your eye) becomes inflamed (swollen) and ulcers (open sores) can form.
  • Iritis: this is a type of uveitis (inflammation of the middle layer of your eye) that causes pain, headaches and watery eyes.

Newborn babies

Contact your GP straight away if you think your baby may have infective conjunctivitis.

Your GP will examine your baby closely to see if they have sticky eye or infective conjunctivitis. Any newborn babies with infective conjunctivitis must be referred to an eye specialist (ophthalmologist) straight away so that their condition can be treated.

Glossary

Conjunctiva
The conjunctiva is the transparent membrane (thin layer of cells) that covers the white part of the eyeball and the inner surfaces of the eyelids.

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

 

Page last reviewed: 13/07/2011

Most cases of infective conjunctivitis do not require medical treatment and will heal without treatment in one to two weeks.

Self-care

There are a number of ways that you can treat infective conjunctivitis at home. The guidelines below should help ease your symptoms:

  • Remove your contact lenses. If you wear contact lenses, take them out until all the signs and symptoms of the infection have gone. Avoid using contact lenses until 24 hours after you have finished a course of treatment, such as antibiotics. If you have glasses, wear these instead.
  • Use lubricant eye drops. These can be purchased over-the-counter (OTC) at pharmacies or they may be prescribed for you. They may help ease any soreness and stickiness in your eyes. Always follow the manufacturer's instructions.
  • Gently clean away sticky substances. When you wake in the morning, you may notice a sticky substance around your eyes. You can gently clean this away from your eyelids and eyelashes using cotton wool soaked in water.
  • Wash your hands regularly. This is particularly important after you have touched your infected eyes and will stop the infection spreading to other people.

Antibiotics

Antibiotics are not usually prescribed for infective conjunctivitis because:

  • antibiotics will make little difference to your recovery from infective conjunctivitis
  • the risk of any complications from untreated infective conjunctivitis is very low
  • about 10% of people who have their infective conjunctivitis treated with antibiotics experience adverse side effects
  • overusing antibiotics to treat minor ailments can make them less effective in the treatment of more serious or life-threatening conditions

You may be advised to delay using any medicine for seven days to see if the condition clears up by itself.

If your infective conjunctivitis is particularly severe or has lasted for more than two weeks, you may be prescribed antibiotics. Some schools or playgroups insist that a child is treated with antibiotics before they can return, although this is rarely necessary . If this is the case, your GP may agree to prescribe antibiotics.

The two main types of antibiotics that may be prescribed are:

  • chloramphenicol
  • fusidic acid

These are described in more detail below.

Chloramphenicol

Chloramphenicol is the first choice of antibiotic to be used for severe infective conjunctivitis. It is usually in the form of an eye drop and is used as follows:

  • Put one drop in the infected eye every two hours for the first two days.
  • Put one drop in the infected eye every four hours for the next five days.

You only need to use the drops while you are awake. If your symptoms improve within the first five days, continue to use the eye drops for another two days.

If eye drops are not suitable for you, you may be prescribed this antibiotic as an eye ointment instead.

Fusidic acid

Fusidic acid may be prescribed if chloramphenicol is not suitable for you. For example, fusidic acid may be better for children or the elderly as it does not need to be used as frequently. It is also the preferred treatment for women who are pregnant.

Fusidic acid comes in the form of eye drops, which are normally used twice a day for seven days.

Side effects

If you have been prescribed eye drops, your vision may become blurred shortly after using them. Do not drive or operate machinery straight after using eye drops. Before doing so, always make sure that your vision is clear.

Both chloramphenicol and fusidic acid do not usually cause side effects, although they can cause a slight stinging or burning sensation in your eye. This feeling should not last long.

Further treatment

If you still have symptoms after two weeks, it is very important to go back to your GP. Also contact your GP immediately if you experience any of the following symptoms:

  • moderate to severe eye pain
  • photophobia (sensitivity to light)
  • loss of vision
  • intense redness in one or both of your eyes

When you return to your GP, they will check your diagnosis is correct by asking you about your symptoms and possibly performing a swab test

Your GP may suggest that you are tested for sexually transmitted infections (STIs). Some STIs, such as chlamydia, can cause infective conjunctivitis. If chlamydia is the cause of your infective conjunctivitis, your symptoms may last for several months.

Your GP may carry out the test for STIs or may refer you to a sexual health clinic. The tests usually involve using a swab (a small cotton bud) to collect cells from inside your vagina or the end of your penis, and taking a sample of urine.

Glossary

Conjunctiva
The conjunctiva is the transparent membrane (thin layer of cells) that covers the white part of the eyeball and the inner surfaces of the eyelids.

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some others are good for you.

Antibiotics
Antibiotics are medicines that can be used to treat infections caused by micro-organisms, usually bacteria or fungi.

 

Page last reviewed: 13/07/2011

If your infection has been caused by a sexually transmitted infection (STI), especially chlamydia, it may cause your conjunctivitis to last for several months rather than weeks.

If you have infective conjunctivitis that has been caused by bacteria or a virus, complications can occur but are rare.

Bacterial conjunctivitis

Infective conjunctivitis caused by any type of bacteria can cause a number of complications, particularly in babies born prematurely (before week 37 of pregnancy). Possible complications include:

  • Meningitis: an infection of the meninges (the protective layer of cells that surrounds the brain and spinal cord). This is potentially a very serious illness that, in severe cases, can be fatal.
  • Cellulitis: an infection of the deep layer of skin and tissue that causes the skin on the surface to become sore and inflamed (swollen). It is usually easily treated with antibiotics.
  • Septicaemia: this is more commonly known as blood poisoning. This condition occurs when bacteria get into the bloodstream and attack the body's tissues.
  • Otitis media: this is a short-term ear infection. It affects around 25% of children who have had infective conjunctivitis caused by the haemophilus influenzae bacteria.

Punctate epithelial keratitis

Keratitis is when your cornea (the clear layer at the front of your eye) becomes inflamed. Sometimes, ulcers (open sores) form on the cornea. This can be painful and make your eyes sensitive to light.

Punctate epithelial keratitis is when small holes appear in the conjunctiva (the clear layer of cells that covers the white part of your eyeball and the inner surfaces of your eyelids). This can develop as a complication of conjunctivitis after your infection has cleared up. It may last for several weeks before getting better without further treatment.

Neonatal conjunctivitis

In newborn babies (neonates) who are up to 28 days old, infective conjunctivitis can lead to a severe and rapidly progressive eye infection. If this is not treated, it can result in permanent damage to your child's vision.

If your newborn baby is found to have infective conjunctivitis, they will be referred immediately for specialist assessment and treatment. Their condition will be closely monitored. Complications are rare and most babies make a full recovery from infective conjunctivitis.

After having infective conjunctivitis caused by chlamydia, 10-20% of infants may develop pneumonia (inflammation of the tissues in the lungs). This is a potentially life-threatening condition in young babies and may require treatment in hospital.

Glossary

Conjunctiva
The conjunctiva is the transparent membrane (thin layer of cells) that covers the white part of the eyeball and the inner surfaces of the eyelids.

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and others are good for you.

Brain
The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.

Lungs
The lungs are a pair of organs in the chest that control breathing. They remove carbon dioxide from the blood and replace it with oxygen.

Page last reviewed: 13/07/2011

The best way to stop infective conjunctivitis spreading is to thoroughly wash your hands after touching or treating your infected eyes.

If you do not have the infection but someone close to you does, wash your hands every time you come into contact with them. Avoid sharing towels, pillows and flannels to prevent the infection from spreading.

Should I keep my child home from school?

You do not need to keep your child off school if they have conjunctivitis, unless they are feeling particularly unwell.

If there are a number of cases of conjunctivitis at one school or nursery, you may be advised to keep your child away from school until their infection has cleared up. However, this is not usually necessary.

Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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