Health + Prevention

Conjunctivitis, styes, eyelid infection, etc.: The most common eye infections.

Everything you need to know: Causes, treatment and prevention

21 November 2022
  • Conjunctivitis, styes, eyelid infection, etc. The most common eye infections.

It can be very unpleasant and disconcerting if your eyes start to itch, burn or go red. Eye infections like conjunctivitis, styes and eyelid inflammation are more common than you’d think and have a number of possible causes. BETTER VISION explains: What are the most common eye infections? How does an infection develop? What causes infections, what treatments are available and what’s the best way of preventing them?

With the right treatment, most eye infections can be cured in next to no time. However, given that our eyes and faces are rather sensitive, even the slightest symptoms of an eye infection – like severe itching or burning – can be a real nuisance. The good news is, the most common eye infections can be prevented very easily. We’ll tell you how it works.


Close up of the red eye of a man affected by an infection, conjunctivitis
  • Symptoms of conjunctivitis:

    The symptoms of conjunctivitis include red eyes, burning eyes, itching, swollen conjunctiva, pressure on the eyes, a severe light sensitivity and/or eyelids stuck together due to secretions.

  • Causes of conjunctivitis:

    Conjunctivitis is caused by bacteria (chlamydia, haemophilus influenzae, pneumococcae, gonococci, staphylococcus), viruses (herpes, Adenovirus, measles, rubella and chickenpox), parasites (fly larvae, worms), allergies (rhinoconjunctivitis, normally linked to hayfever) and external stimuli. Non-infectious causes include corrosive substances, injuries and foreign bodies in the eyes, as well as smoke, UV light, dust or draughts. A disease affecting the tear ducts can also trigger conjunctivitis. Conjunctivitis is one of the most common eye infections out there.

  • Treating conjunctivitis:

    Treatment differs depending on the cause of the conjunctivitis. A distinction is made between bacterial, viral and allergic conjunctivitis. It’s advisable to stop wearing contacts until the infection has cleared up.

    Bacterial conjunctivitis:
    A minor case of bacterial conjunctivitis normally clears up on its own and does not require treatment. Antibiotic eye drops or gels can be prescribed to speed up the healing process. Severe cases of conjunctivitis are treated with a course of antibiotics.

    Viral conjunctivitis:
    Normally, viral conjunctivitis can’t be treated without the right medication. Cold compresses and artificial tears can be used to ease symptoms. If the infection was caused by a herpes virus, Aciclovir can be prescribed.

    Allergic conjunctivitis:
    In the case of allergic conjunctivitis, the allergen must first be determined. Only then can treatment with so-called mast cell stabilizers and antihistamines be started, which will help the patient’s immune system deal with the allergens. Decongestant eye drops containing cortisone can be prescribed to ease symptoms; artificial tears and cold compresses can also help.

  • Preventing conjunctivitis:

    There’s virtually no way of preventing viral or bacterial conjunctivitis. If the conjunctivitis is triggered by external stimuli (smoke, wind, UV radiation), the best approach would be to avoid coming into contact with them. Try wearing sports glasses with sight protection, or sunglasses.


Close-up of a child's eye stye. Ophthalmic hordeolum disease
  • Symptoms of styes:

    People with styes complain of pain and pressure in the affected area. It can affect both the upper and lower lids, no matter which gland has become infected. Added to that is the distinction between internal and external styes: the inner stye (Hordeolum internum) is located inside the eyelid. While it’s often invisible, it does result in a very red and swollen eyelid. An external stye, however, (Hordeolum externum) is clear to see.

  • Causes of styes:

    A stye is a purulent inflammation of the glands on the eyelid, triggered by a bacterial infection (normally staphylococcus, and in rarer cases A-streptococci). The abscess is shaped like a small grain, hence the name hordeum, which means “barley” in Latin. There are various possible causes for an infection, such as a lack of hygiene. Various risk factors can also cause a stye. They include diabetes mellitus or a compromised immune system. In both cases, the glands don’t work as they should, meaning the bacteria can multiply more quickly.

  • Treatment for styes:

    Patients should ensure they don’t try to squeeze out the stye with their fingers as the pus will cause the infection to spread. Styes will generally clear up on their own and don’t require any special treatment. That said, radiation with a heat lamp, antiseptic eye gels and antibiotic eye drops can all help the healing process. If the stye has not shrunk after several days, you will need to consult an eye doctor.

  • Preventing a stye:

    A stye is a bacterial infection, which means good hygiene and eye care can reduce the risk of infection. In other words, make a point of regularly washing your hands, particularly before touching your eyes. A compromised immune system is another risk factor. All prevention measures are in fact relevant here, e.g. keeping a balanced diet and getting regular exercise.

Eyelid infection (blepharitis)

Eyelid infection (blepharitis)
  • Symptoms of eyelid infections:

    Red, crusty, swollen, itchy and/or burning eyelids normally point to an eyelid infection. In addition, the feeling of having a foreign body in the eye, shiny eyelid margins, dandruff at the base of the eyelashes, and eyelashes that fall out or are stuck together in the morning, are all possible signs of blepharitis.

  • Causes of eyelid infections:

    Eyelid infections are caused when the sebaceous glands inside the eyelids become blocked. This can be triggered by irritation, an infection or surplus production of grease. The special glands below the eyelashes discharge grease that is spread over the eyes every time we blink, allowing the eyelids to glide over the eye with ease. If too much of this grease is produced, the glands will stick together. Eye doctors refer to this as a non-infectious eyelid inflammation, or seborrhoea. More often than not, an eyelid infection is caused by several different things. The “triple S syndrome” is what doctors call the process whereby an eyelid infection and seborrhoea occur at the same time as an infection with staphylococcus and dry eyes (Sicca syndrome). Dust, smoke and draughts can also give rise to blepharitis.

  • Treatment for eyelid infections:

    The infection is diagnosed by examining the inside of the eyelid, the cornea or taking a smear of the eyelid margin. The eye doctor will then normally prescribe an antibiotic gel or tablets. If the tear film is compromised, it may be advisable to prescribe a tear substitute (e.g. eye drops). Patients can speed up the healing process by taking greater care when cleaning their eyelids. Apply warm, moist compresses to the eyes daily for up to ten minutes to help dissolve the stubborn secretion that builds up in the glands. Next, use a cotton bud to wipe up, towards the lashes and remove the liquefied substance.

  • Preventing eyelid infections:

    You can keep an eyelid infection at bay by avoiding the external stimuli that cause it. These include irritants like dust and smoke, as well as other impurities in the air. Avoiding draughts also helps prevent acute blepharitis. If you suffer from a chronic eyelid infection, you can keep symptoms at bay by cleaning your eyelids every day.

Corneal infection (keratitis)

Close up of male brown bloodshot eyes and redness with vessels. Loremipsum
  • Symptoms of corneal infections:

    The symptoms of corneal infections vary depending on the cause and point of origin. As the conjunctiva is also often inflamed (conjunctivitis), people with corneal infections often suffer from red, watery eyes that secrete a watery or pus-like substance. With a normal cornea, the infection will normally remain on the surface of the cornea. In the case of superficial infection, only the external layer (epithelium) of the cornea becomes slightly hazy. However, if the corneal layer below it (the stroma) becomes inflamed, say as a result of an injury, this will lead to significant clouding in the form of a white spot. If the innermost layer (endothelium) becomes inflamed, the cornea can swell. Keratitis often causes intense pain and severely debilitates vision.

  • Causes of corneal infections:

    The primary cause is a bacterial infection, e.g. not properly caring for your contact lenses. Typical germs include pneumococcae, staphylococcae and streptococcae. Diseases such as diabetes mellitus or a compromised immune system increase the risk of a bacterial corneal inflammation. Viruses can also trigger an infection. The most common are adenovirus, herpes simplex virus and varicella zoster virus (chickenpox virus). In very rare cases, corneal infections can also be caused by a fungus (candida albicans). The pathogens often find their way into the eyes with foreign bodies or in contaminated water, e.g. swimming pool water or contact lens care products.

    Non-infectious triggers include mechanical irritants (injuries, contact lenses, eyelashes and other foreign bodies), alcohol addiction, too many hours spent working at a computer, and insufficient tear film. If the tear ducts don’t produce enough tear fluid or the quality of the tear film is not high enough, this can cause chronically dry eyes and thus roughness of the corneal surface. This can also be exacerbated by eyelid deformities as this will mean that tear film is not properly distributed over the eye.

  • Treatment for corneal infections:

    A range of treatment methods can be used depending on the cause of a corneal infection.

    Bacterial infections
    A bacterial corneal infection can be effectively treated with antibiotic eye drops. The drops will limit the spread of the pathogen, and give quick relief.

    Viral infections
    Viral infections are normally treated with an eye cream and tablets. Many eye doctors opt for Aciclovir, which is used to treat both chickenpox and herpes simplex viruses.

    Chronically dry eyes
    In this case, patients are normally given special eye drops that stabilize tear film and keep the eyes moist.

  • Preventing a corneal infection:

    The most common cause of a bacterial corneal infection is poor hygiene when putting in, taking out or storing contact lenses. Contact lens wearers can thus keep bacterial keratitis at bay by taking proper care of their contacts. This includes:

    • Wearing contact lenses only as long as the manufacturer recommends
    • Observing the instructions on the cleaning solutions
    • Regularly replacing the contact lens case
    • Thoroughly washing your hands with soap before touching the lenses
    • Cleaning the lenses once again if they’ve been sitting in the cleaning solution for more than a week
    • Never using cleaning solutions many times over

Uveitis, inflammation of the uvea

Closeup of irritated or infected red bloodshot eyes - uveitis
  • Symptoms of uveitis:

    The signs of uveitis are red eyes, an increase in tear fluid, greater glare, blurred vision and pain when exerting pressure on the eye. Patients often complain of seeing fluff, flakes or schlieren.

  • Causes of uveitis:

    Uveitis is an umbrella term for a range of diseases that affect the inner eye and cause parts of the uvea to become inflamed. There are so many different causes that we cannot look at them all in detail here. Eye doctors distinguish between front (anterior), central (intermediary) and back (posterior) uveitis.

  • Treatments for uveitis:

    There is a range of possible treatment options depending on the type of uveitis. Uveitis treatment aims to deal with the inflammation in the eye to reduce symptoms. This is where eye drops that are used to dilate the pupils (e.g. Atropin, Scopolamin and Tropicamid) and contain anti-inflammatories come into play. If the uveitis was caused by an infection, antibiotics or antiviral medication can help.

  • Preventing uveitis:

    There’s currently no way of preventing uveitis.

Eye infection, infection

eye with infection
  • Symptoms of eye infections:

    The symptoms of an infection are determined by their cause. As there are many possible causes for an eye infection, there are no standard symptoms. With many eye infections, however, the conjunctiva becomes inflamed, the patient experiences a slight or severe burning sensation and a watery, slimy or purulent discharge. Bacterial infections usually cause the eyes to go red, while viral infections make them turn pink.

  • Causes of eye infections:

    An eye infection is caused by viruses, bacteria, parasites or fungi. Allergies can also cause eye infections. The most common cause of an eye infection are viruses, which normally manifest on the inside of the eyelid or the surface of the eye. Histoplasmosis and the herpes virus are some of the most common causes of eye infections, as are the STDs chlamydia and gonorrhoea.

  • Treatment for eye infections:

    An infection is treated in a certain way depending on what’s causing it. Depending on the severity of the infection, it can be treated with antibiotics or eye drops. This treatment option will be considered if the symptoms do not clear up in three days. Bacterial and many viral infections normally clear up without any treatment. Patients suffering from acute symptoms usually find relief through cooling. Home remedies such as Eyebright – available as drops or tea – can reduce symptoms. If the patient is suffering from an allergic eye infection, the allergy can be treated with antihistamines. They will drastically reduce allergic reactions in the body such as itching and sneezing.

  • Preventing eye infections:

    Eye infections are normally caused by touching your eyes with dirty hands. In this case, the most effective form of prevention is care and proper hygiene. If you come into contact with an infected person or potentially infected objects, you should wash your hands regularly and not touch your face or rub your eyes.

Please note:  Even if most of these symptoms seem harmless, they may also indicate a serious illness. If in doubt, or if the symptoms get worse, please see a doctor immediately. This is especially crucial if you find it difficult to figure out what is causing your symptoms. A doctor will be able to make a definite diagnosis by taking your medical history.

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