Truths and false myths of conjunctivitis

If there is any pathology related to the eyes that is known and easily recognizable, it is conjunctivitis. When we see a person with very red eyes, we quickly associate it with this condition. But is it always like this?

What is conjunctivitis?

By definition, conjunctivitis is inflammation of the conjunctiva, which is the transparent layer that covers the white part of the eye. Inflammation causes the conjunctiva to become irritated and the eyes to adapt to this characteristic red color. It is usually also accompanied by a constant tearing and a feeling of discomfort, such as sand inside the eye.

However, not always when the eye takes on this reddish hue does it mean that we have conjunctivitis. There are multiple factors that can cause redness of the eye: entry of dust or a foreign body, spending many hours in front of the screen, and so on.

Is conjunctivitis contagious?

It depends. There are four main types of conjunctivitis: irritative, allergic, viral and bacterial. Irritant or allergic conjunctivitis is not contagious, but viral and bacterial conjunctivitis are.

Let’s see what each of them consists of.

Types of conjunctivitis

  • Irritant conjunctivitis: When we spend a lot of time in the pool or on the beach, both chlorine and sea salt can irritate the conjunctiva and cause inflammation.
  • Allergic conjunctivitis: The pollen released by the flowers in the spring can cause this type of conjunctivitis.
  • Bacterial conjunctivitis: It is caused by different types of bacteria. It is distinguished mainly because it presents a rather purulent secretion and the sensation of having the eye glued. It is highly contagious
  • Viral conjunctivitis: Produced by a virus. It is usually accompanied by other symptoms such as inflammation of the eyelids, sensitivity to light, fever, etc. It is also very contagious.


For irritative and allergic conjunctivitis there is no specific treatment beyond the application of artificial tears to help calm the symptoms. In the case of highly contagious conjunctivitis (viral and bacterial) , it is necessary to apply a treatment and perform more specific care.

Once it is confirmed that this is one of these two types, the first thing to take is a series of measures to prevent us from infecting more people: do not share towels, pillows or glasses; wash your hands thoroughly and avoid rubbing your eyes. Second, it is necessary to start the appropriate treatment prescribed by the specialist. Bacterial conjunctivitis is treated with the administration of antibiotic eye drops. In contrast, these eye drops have virtually no effect in the case of viral conjunctivitis. These are usually treated with artificial tears that help clean the eye and antiseptic wipes to wash the area of ​​the eyelids and eyelashes. They are usually infections that usually do not last more than 5 days.


Although generally irritative and allergic conjunctivitis are more associated with the summer months, and bacterial and viral conjunctivitis at colder times of the year, it is essential to always go to the ophthalmologist. Only through a thorough examination can we find out the type of conjunctivitis we suffer from and apply the most appropriate treatment. And above all, if you have any doubts, always go to your ophthalmology center.