Eye infections

Washing hands with soap

Sometimes known as conjunctivitis, eye infections are the result of bacteria, fungi or viruses that invade the eye. Find out about the causes, symptoms and treatments for eye infections, as well as advice on how to help prevent them.

Symptoms of infected eyes

Infections can affect any part of the eyes, including the eyelids, cornea, conjunctiva, and even the retina in the back of the eye. They can be categorised as bacterial, viral or allergic and can present themselves in many different ways:

  • Bacterial: Eyes may produce discharge, look red and feel uncomfortable.
  • Viral: Watery eyes, eyelids may stick together in the morning, itchy eyes, sensitivity to light and redness.
  • Allergic: Watery, itchy eyes, with a runny nose – there may also be a burning sensation in the eyes.

When to seek medical attention

While eye infections can typically be managed at home with the appropriate treatment, be sure to seek medical attention if you experience any of the following:

  • pain in the eyes
  • vision blurring, sensitivity to light or any other vision problems
  • a blister or patch in the eye
  • intense redness in the eye(s)

You should also see a healthcare professional if you have conjunctivitis and any other medical condition or illness – for example, HIV infection, cancer treatment etc.

Causes of eye infections

Conjunctivitis can be caused by types of viruses or bacteria. Other causes can be allergic reactions and exposure to irritants.

Viral conjunctivitis

This type of conjunctivitis is contagious and typically caused by common viruses such as adenovirus (associated with the common cold and bronchitis) and herpesvirus (known for cold sores).

Other symptoms such as a cold, sore throat or infections of the upper respiratory tract can also be present with viral conjunctivitis.

Bacterial conjunctivitis

Common in children, bacterial infections can be caused by exposure to contaminated objects or surfaces, contact with an infected person or spread from sinus or ear infections.

The types of bacteria that cause bacterial eye infection include:

  • Staphylococcus species
  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Moraxella catarrhalis

Allergic conjunctivitis and irritants

Allergic conjunctivitis can be caused by seasonal changes, particularly as a reaction to pollen. If you’re allergic or sensitive to dust mites, moulds or animal dander, it may flare up at any time of the year.

Contact lens wear, smoke, pollutants and chemicals can also cause , as the eye becomes inflamed from allergens or irritants it considers harmful. Taking a break or switching to a different type of lens can help contact lens wearers, while other causes can typically be resolved with over-the counter remedies.

A diagram explaining the difference between a healthy eye and an infected eye

 Treating conjunctivitis

Infective conjunctivitis can be treated with medicinal eye drops containing Chloramphenicol, an antibiotic known for relieving symptoms and clearing up eye infections.

Specific forms of conjunctivitis can be treated in the following ways:

  • Viral conjunctivitis:
    Viral infections tend to be mild and clear up within 7 to 14 days. Anti-viral medication can be prescribed by a doctor to treat more serious forms of conjunctivitis, such as herpes simplex virus or varicella-zoster virus.
  • Bacterial conjunctivitis:
    Mild bacterial conjunctivitis may get better without antibiotic treatment, but antibiotics may be prescribed by a doctor to shorten the illness and settle the infection.
  • Allergic conjunctivitis:
    Allergy medication, including medicinal eye drops, can help relieve symptoms. In addition, products such as our Irritated Eye Drops can help soothe the eyes. Conjunctivitis can be eliminated by avoiding the allergy or irritant and taking preventative measures.

If you’re not sure which type of infection you have, seek advice from a healthcare professional. Always read the label before using a product.

Preventing conjunctivitis

Taking just a few simple steps can help avoid contracting conjunctivitis altogether:

  • wash hands thoroughly and regularly
  • avoid close contact with others while they are contagious
  • avoid sharing towels, tissues, makeup, eye drops and handkerchiefs
  • wear eye protection to protect against chemical and toxin exposure
  • do not share contact lenses or eye wear
  • practise good contact lens hygiene and follow the manufacturer’s instructions
  • avoid touching the eye or rubbing the eye
  • keep contact lens cases, sunglasses, glasses and cases clean

If you have young children, be sure to advise them of how to look after their eyes and practise good hygiene by following these guidelines.

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