CONJUNCTIVITIS 101: CAUSES, SYMPTOMS, TREATMENT, AND PREVENTION

Conjunctivitis, commonly known as “pink eye,” is an infection of the conjunctiva – the thin, transparent membrane that lies over the inner surface of the eyelid, covering the white region of your eye. This mucus membrane lubricates the eye with tears and protects it from germs and infections.

When you have conjunctivitis, your eyes appear red and swollen as the blood vessels in your conjunctiva become inflamed. Often, a sticky discharge oozes out from your eyes.

Both adults and children can get pink eye, although the infection is more common in children. Until your symptoms clear, you should stay away from all forms of social contact.

Pink eye types and causes

There are three main types of conjunctivitis depending upon the cause of infection:

• allergic
• infectious
• chemical

A doctor can often determine whether a virus, bacteria, or allergen is causing conjunctivitis based on the patient’s medical history, symptoms, and an examination of the eye. 

Infectious conjunctivitis

Common types of infectious conjunctivitis include:

• Bacterial conjunctivitis is often caused by the staphylococcal or streptococcal bacteria from your own skin. It usually occurs through physical contact with other people, touching your eyes with unclean hands, insects, sharing makeup or lotions, or simply poor hygiene.
• Viral conjunctivitis is commonly caused by adenoviruses or other contagious viruses associated with the common cold. It can occur if you are exposed to the coughing or sneezing of someone with an upper respiratory tract infection. It can also occur as the virus spreads along the body’s own mucous membranes, which connect the lungs, throat, nose, tear ducts, and the conjunctiva. This could happen even when you have a cold yourself and blow your nose too hard.
• Ophthalmia neonatorum is a severe form of bacterial conjunctivitis that occurs in newborns during the neonatal period (first 4 weeks of a child’s life). If not treated immediately, this condition could lead to permanent eye damage and even blindness. Ophthalmia neonatorum occurs when an infant is exposed to a sexually-transmitted disease in the mother’s birth canal. The infection may be bacterial, chlamydial, or viral.

Viral and bacterial pink eye is very contagious and can spread easily from person to person.

Allergic conjunctivitis

Allergic conjunctivitis commonly occurs in people who already have some form of seasonal allergies. Pink eye caused by eye allergies, like other types, can be triggered by allergens including pollen, animal dander, and mold.

It is also possible to develop another type of allergic conjunctivitis called giant papillary conjunctivitis.

It is generally caused by the presence of foreign bodies in the eye. You can develop giant papillary conjunctivitis if you wear hard contact lenses or soft ones that are not replaced frequently enough.

Loose stitches or exposed sutures in your eye can also increase your risk.

Chemical conjunctivitis

Chemical conjunctivitis can be caused by irritants like:

• air pollutants
• chlorine in pools
• exposure to other chemicals

Chemical conjunctivitis is not contagious, and you may be allowed to remain at work or school with your doctor’s approval if the symptoms are not serious.

Is pink eye contagious?

Bacterial and viral conjunctivitis are both highly contagious, and you may be contagious for up to two weeks after your symptoms first appear.

Pink eye that is caused by bacteria can spread as soon as the symptoms appear, and until 24 hours after antibiotics are started. Conjunctivitis caused by a virus is generally contagious even before the symptoms appear.

In general, pink eye can remain contagious if you are tearing or showing any form of symptoms. Allergic conjunctivitis and chemical conjunctivitis, on the other hand, are not contagious.

How does conjunctivitis spread?

The incubation period (the time between catching the virus and symptoms of the disease beginning to appear) for bacterial conjunctivitis is about 24 to 72 hours and 5 to 12 days for viral conjunctivitis.

If you touch something with bacteria or virus on it and then touch your eyes with the same eye, you can develop pink eye. While most bacteria can survive for a few hours to days on surfaces, viruses can last for as long as months.

The infection can spread through contaminated fomites, coughing, sneezing, or any close contact like a handshake or a hug.

If you wear contact lenses for extended durations, you are at an increased risk of developing pink eye. This is because bacteria can live and grow on these lenses, and unclean lenses can often capture allergens as well.

Symptoms of pink eye

Different types of pink eye can have slightly different symptoms.  The two main symptoms are usually:

• eye redness – caused due to the inflammation and widening of the blood vessels in the conjunctiva
• a discharge – inflammation causes the glands in the conjunctiva to become overactive, producing extra water and mucus

Inflammation or irritation of the eye doesn’t always mean conjunctivitis. Your symptoms could be caused by seasonal allergies or a stye. Spending a long time in the swimming pool without protective eyewear can also cause your eyes to redden due to the chlorine.

Still, it is a good idea to consult a doctor if you start experiencing any of the following:

• a feeling that something is in your eye
• pink or red-toned eyes
• puffy eyelids
• itchiness in your eyes
• pain or a burning sensation in your eyes
• abnormal amount of tears
• a green/yellow discharge dripping from your eyes
• a gooey buildup around your eyelids while you sleep
• crusty appearance of your eyelashes
• blurry or hazy vision
• being extra sensitive to light

Bacterial conjunctivitis is more commonly associated with a gooey discharge. Viral conjunctivitis, on the other hand, often occurs with symptoms of a cold or flu, with a discharge that is usually watery.

Allergic conjunctivitis can occur with other symptoms of allergies, such as an itchy nose, a scratchy throat, difficulty breathing, or asthma.

Pink eyes can develop in one or both eyes and can give you an uncomfortable feeling, especially if you wear contacts. If possible, you should avoid wearing contacts while you show any symptoms of pink eye.

Diagnosis of conjunctivitis

Often, your ophthalmologist can diagnose conjunctivitis simply by an eye examination. Based on your symptoms, the doctor can determine whether the infection is viral, bacterial, or allergic.

Medical history

A medical professional can often rule out many causes of conjunctivitis simply by asking about your symptoms. They may ask whether you’ve come into contact with someone who has conjunctivitis, or if you came in contact with any irritant or allergen.

They might also ask if you’re experiencing the symptoms of a common cold, hay fever, or asthma.

Eye examination

Doctors generally examine conjunctivitis by using a slit lamp. During the exam, your doctor shines a thin beam of light into your eye and examines your conjunctiva, the iris, the cornea, and the sclera – the white of the eye, under a microscope.

Doctors also check to see if the conjunctivitis has affected your vision by conducting a visual acuity test.

If you have had pink eye for more than two or three weeks and it has not gone away on its own or with the help of treatment, your doctor may perform an eye culture. This helps them determine the type of conjunctivitis and the most effective treatment.

Treatment for pink eye

Treatment for conjunctivitis depends on what is causing it – a bacteria, virus, or some allergen.

Treatment for bacterial conjunctivitis

Mild bacterial conjunctivitis often improves in 2 to 5 days without treatment but can take up to 2 weeks to go away completely. In general, your doctor may prescribe you a topical antibiotic as eye drops or an ointment for bacterial conjunctivitis.

Treatment for viral conjunctivitis

Viral conjunctivitis is generally mild in nature and is self-clearing. The infection usually goes away in 1 to 2 weeks without any treatment but may take several weeks in some cases.

Sometimes, the herpes simplex virus or the varicella-zoster virus (shingles) can cause viral conjunctivitis, in which case you should consult a doctor.

It is not responsive to antibiotics, and a doctor may prescribe antiviral medication to treat more serious cases. Common symptoms can often be relieved with a cold compress and artificial tear solutions.

Treatment for allergic conjunctivitis

Allergic conjunctivitis usually clears itself by removing the allergen, like pollen or animal dander, from the patient’s environment. Common treatments include:

• topical antihistamines
• prescription eye drops
• a combination of drugs

Allergic conjunctivitis is often accompanied by other symptoms of allergy, such as a runny nose or itchy throat. In such cases, the doctor may prescribe an oral dose of antihistamines to treat other symptoms.

Treatment for chemical conjunctivitis

Most people don’t need treatment for chemical conjunctivitis. After the eye is cleaned thoroughly to remove any toxic substance, artificial tears or some topical medication may be used to reduce redness and inflammation.

The best way to treat chemical conjunctivitis is by avoiding exposure to the chemical irritant causing the inflammation.

Home remedies

Pink eye typically gets better when the irritant is no longer actively present, meaning that the infection is gone or the allergic reaction has stopped.

In the meantime, some easy home remedies can help reduce discomfort and ease any mild pain you might be feeling.

• Use a cool compress. Pink eye causes inflammation around the eye, which can lead to irritation and pain. A cool compress can help reduce this discomfort by soothing the inflamed blood vessels of the conjunctiva. To make a cool compress, simply soak a clean towel in cold water and wring out any excess water, then hold the cloth over the affected area for a few minutes. Make sure to not reuse the washcloth. Wash used towels in hot water.
• Eye drops. To soothe the irritation or burning sensation in the eye, people can cause artificial tears. These are available as OTC medication.
• Take supplements to boost the immune system. Supplements that contain nutrients such as vitamins A, C, D, and zinc boost the immune system. Zinc supplements are often recommended for preventing eye infections, including pink eye.

Conjunctivitis is often self-clearing and does not require any treatment. However, if you are experiencing any severe symptoms, it is advised to see a doctor.

Eye doctors are best equipped to give you a complete evaluation, and to determine if treatment is necessary.

How to manage pink eye?

If you have conjunctivitis, you can limit its spread to other people by taking the following steps:

• Wash your hands thoroughly with tepid water and soap. In case soap and water are not available, use an alcohol-based hand sanitizer.
• Avoid touching your eyes, especially if only a single eye of yours is infected. This can cause the condition to worsen and spread to your other eye.
• Clean any discharge that may drip from your eyes several times a day using a clean, wet washcloth or a fresh cotton ball. Throw the cotton balls after use, and wash used washcloths with hot water and detergent.
• Wash pillowcases, sheets, washcloths, and towels often with hot water and detergent.
• Stop wearing contact lenses until the infection clears out. Throw away your old lenses to prevent reinfection.
• Do not use swimming pools. The chlorine in pools can worsen the condition.
• Avoid contact with people until all symptoms clear out.

If you are around someone with conjunctivitis, you can reduce the risk of infecting yourself by taking these steps:

• Wash your hands often, especially after contact with an infected person.
• Avoid touching the belongings of the infected person.
• Do not share items used by the infected person, especially pillows, washcloths, towels, eye drops, makeup, contact lenses, or eyeglasses.

For anyone infected with pinkeye, it is best to be isolated from any social contact for about 2 weeks to ensure that the infection has cleared out.

In a nutshell

Conjunctivitis, commonly called pink eye, is an infection of the conjunctiva that can be caused by a bacteria, virus, or an allergen. 

 It results in the swelling of blood vessels in the conjunctiva – the thin, transparent membrane that covers the white of your eyes – causing your eyes to appear swollen. The infection is very common and highly contagious in case of viral or bacterial pink eye.

The infection usually goes away by itself within a few days, although certain treatments can help ease your symptoms.