Infectious conjunctivitis

What is infectious conjunctivitis?

Conjunctivitis is an inflammation of the conjunctiva, which is the mucous membrane that covers the inside of the eyelids. It normally affects both eyes at the same time, although it can sometimes begin in one eye and then transfer to the other after a day or two. The condition in such cases is asymmetrical and more severe in the first eye. Conjunctivitis caused by an infectious agent (bacterial or viral) is normally acute. There are several causes and it is a very common condition that is not generally severe, although it can be very unpleasant.

What causes infectious conjunctivitis?

• Viral conjunctivitis

Viral conjunctivitis is the most frequent cause of infectious conjunctivitis. It is often connected to colds and the most frequent cause is viruses of the adenovirus group. This type of conjunctivitis is very contagious, and can quickly spread from person to person and even cause epidemics. It is transmitted directly via contaminated hands or the use of contaminated objects (towels, pillows, toys, etc.).

• Bacterial conjunctivitis

With this type of conjunctivitis, the infection is caused by bacteria. These microorganisms can originate in the skin of the patient, the upper respiratory tract, or be transmitted by another person who has conjunctivitis. In some rare cases, conjunctivitis is caused by very aggressive germs, such as pseudomona aeruginosa in lens containers, C. diphtheria in children between 1 and 4.

What are the symptoms?

Viral conjunctivitis

• Eye reddening, sometimes accompanied by haemorrhaging of the conjunctiva.
• The symptoms are often similar to those of bacterial conjunctivitis, generally accompanied by cold symptoms.
• There may be an increase in the size of the lymph nodes, which can cause pain around the ears and the neck.
• This type of conjunctivitis may also spread and affect the cornea (keratitis), which can lead to reduced vision and more intense symptoms which lead to a longer evolution.

Bacterial conjunctivitis

This affects both eyes equally. The symptoms are usually less severe, provided there are no complications, and include:

• Discomfort to the eyelids
• Eye reddening
• Itchiness and foreign body sensation (like having sand in your eye)
• Secretions, normally with lots of mucous, which can stick to the eyelids when you wake up in the mornings.
• It does not cause considerable discomfort. It can occasionally cause clouded vision due to secretions.
• If considerable pain is experienced or a reduction in vision, then other pathologies should be ruled out.

How is conjunctivitis diagnosed?

Conjunctivitis is diagnosed through a clinical evaluation carried out by the ophthalmologist. If it is suspected then there is a specific test to look for the adenovirus in the conjunctiva called ADENO PLUS. A sample of conjunctival discharge is taken for cultivation in the lab in cases of severe bacterial conjunctivitis or with an unusual development.

How is it treated?

Viral conjunctivitis

• There is no effective treatment for viral conjunctivitis.
• Normally lubricating treatments are used to ease the discomfort (eye drops, ointments, washing out the eyes with saline solution). Anti-inflammatory drugs can be used to improve the symptoms and general antibiotics in eye drops and eye ointment to prevent bacterial infection, although none of this reduces how contagious it is or how long the symptoms last for.
• It is very contagious which is why it is essential to follow very strict hygiene regulations regarding washing hands, face and all objects that you suspect may be infected.
• When the cause is a herpes virus, a specific antiviral treatment is required.
• In any case, only an ophthalmologist can prescribe corticosteroids.

Bacterial conjunctivitis

• Is normally treated with broad spectrum antibiotics in eye drop or ointment form.
• In addition, scabs and secretions should be removed by rinsing with saline solutions.

What should I look out for?

In serious cases or those resistant to treatment, or if there is a deterioration in vision, you should contact your doctor again, even if you are following the correct treatment.

What precautions should I take?

• You should follow very strict hygiene rules with regard to washing hands and it is best not to share towels and avoid close physical contact with those suffering from conjunctivitis, regularly wash your hands and avoid contact between the eyedrop container and your eyes.
• Do not rub your eyes, as it can easily spread from one eye to the other.
• Remove scabs and secretions by washing your eyes out with saline solution.
• Throw away all opened eyedrops once the treatment has finished.
• Keep utensils and objects of personal use away from the rest of the family (toys, cosmetics, cutlery, towels, glasses…).
• Those with conjunctivitis should avoid crowded events or places where there are lots of people (schools, crèches, offices, gyms, swimming pools).
• Avoid physical contact with the eye. When this is not possible, wash your hands after contact and do not touch your eyes with your hands or with potentially contaminated objects.
• Patients should not share any medication or implement that has been prescribed for treatment with the sick person, as it can become a mechanism for transmission.
• Patients should be considered contagious until the symptoms disappear.

How does conjunctivitis usually develop?

The vast majority of conjunctivitis improve spontaneously after a few weeks. Even with treatment, there can be a worsening in the first days and the other eye can be affected. Treatment does not shorten the duration of viral conjunctivitis. Viral conjunctivitis follows a clinical development (normally between 2 and 4 weeks) and medication can help to reduce symptoms, but it does not reduce the time needed to resolve the symptoms.

As a result, for a couple of months you may experience a foreign body sensation (like sand in your eye) or occasional reddening. With time this normally disappears. In these cases you are advised to use artificial tears and evaluate how it evolves. In the most complicated cases, between weeks 3 and 4 small marks may appear on the cornea that can reduce vision. This complication lasts longer than the others, for a few months, and can leave other marks and scars on the cornea, meaning that occasional tests are required until the symptoms are solved.