Viral Conjunctivitis
Written by Ada’s Medical Knowledge Team
Updated on
What is viral conjunctivitis?
Conjunctivitis is the name for inflammation of the conjunctiva, which is the thin layer of tissue on the inside of the eyelids and which covers the white part of the eye. Also known as pink eye, conjunctivitis is often caused by a virus, for example, one of the varieties that causes the common cold, though it can be caused by bacteria (see bacterial conjunctivitis) or allergies (see allergic conjunctivitis) too. When pink eye is caused by a virus, it is called viral conjunctivitis. Like all types of pink eye, viral conjunctivitis is common but not usually serious. 1 2 3
Viral conjunctivitis typically begins in one eye and then spreads to the other. The main symptoms of viral conjunctivitis include: 4 5 6
- Pinkness or, often, intense redness of the eye
- Burning, a sensation of grittiness, or mild pain or discomfort in the eye
- Watery discharge from the eye
- Swollen and/or reddened eyelids
- Other symptoms of viral infection, e.g. sore throat, runny nose, and other cold symptoms
Most mild cases of viral conjunctivitis clear up on their own within a couple of weeks, without any specific treatment. Cleaning the eyes with water and a clean cloth or sterile pad, applying warm or cool compresses, and using lubricating eye drops, also known as artificial tears, may help to relieve symptoms. However, antiviral medications may be recommended for more serious cases of viral conjunctivitis. Antibiotics are not useful for treating viral pink eye. 2 4 5 6
Generally, people make a complete recovery, and viral conjunctivitis does not cause any complications. However, cases caused by certain viruses, such as herpes simplex, the cold sore virus, or varicella-zoster, the virus that causes chickenpox and shingles, can be serious and may cause lasting eye problems if not managed effectively. 1 Furthermore, if viral conjunctivitis occurs in newborn babies or people with weakened immune systems, such as those who have HIV or are undergoing treatment for cancer, it can be severe, and medical advice should be sought without delay. 2 6
In addition, anyone experiencing severe symptoms should see a doctor immediately. These include: 2 5 6
- Intense pain in the eye
- Extreme redness, especially in one eye only
- Inability to open the eye
- Severe sensitivity to light
- Difficulty seeing
If symptoms are mild but do not improve within a week or so, medical advice should also be sought.
Viral conjunctivitis can affect people of any age. It is highly contagious, which means that it can be spread easily from person to person. For this reason, it is important for people who have viral conjunctivitis to take steps to avoid passing on the infection to others, such as practicing good hygiene (see the section on prevention).
Symptoms of viral conjunctivitis
Viral conjunctivitis often begins in one eye and spreads to the other within a day or two. Symptoms may include: 4 5 6
- Pinkness or, typically, intense redness of the eye
- Burning, a sensation of grittiness or mild pain or discomfort in the eye
- Watery discharge from the eye, sometimes with a small amount of mucus
- Crustiness around the eyelids upon waking in the morning
- Swollen, red eyelids
- Slight sensitivity to bright light
- Swelling of the lymph nodes in front of the ears
- Other symptoms of viral infection, e.g. runny nose, sore throat and cough in the case of a cold
The Ada app can help you check your symptoms. Download the free app or find out more about how it works.
Mostly, viral conjunctivitis causes mild symptoms and does not affect a person’s vision, other than causing slight blurriness when discharge has built up on and around the eye. 7 Depending on the type of virus causing the infection, there may be additional symptoms, or only one eye may be affected. When only one eye is affected, it is called unilateral conjunctivitis.
If symptoms are severe or vision is impaired, it is important to contact a doctor without delay. It is also extremely important to see a doctor if any signs of viral conjunctivitis are present in a newborn baby or a person whose immune system is weakened.
Causes of viral conjunctivitis
The most common cause of viral conjunctivitis is infection with adenovirus, the group of viruses that cause the common cold and many other upper respiratory infections. 4 3 6
An adenovirus may cause conjunctivitis without causing any other symptoms in the body. However, in some cases adenoviral conjunctivitis may manifest as: 3 6
- Pharyngoconjunctival fever: Which is common, mild and often seen in children and young adults who have recently had a cold or respiratory infection. Symptoms may include sore throat, fever and headache.
- Epidemic keratoconjunctivitis: Which is less common, can be severe, affects the front of the eye (cornea) and may cause long-lasting vision difficulties. Also known as viral keratoconjunctivitis.
Less common causes of viral conjunctivitis include: 4 3 6 7
- Enteroviruses
- Herpes simplex virus, the cold sore virus, which usually affects only one eye
- Herpes zoster ophthalmicus, associated with shingles
- Molluscum contagiosum, also known as water warts
- Measles
- Mumps
- Rubella, also known as German measles
- Infectious mononucleosis
- HIV
Conjunctivitis caused by some of the above, such as herpes simplex and herpes zoster, can be severe, and a person may need to be referred for specialist treatment to prevent complications.
Diagnosis of viral conjunctivitis
When symptoms are mild, a diagnosis of viral pink eye can often be made without seeing a doctor, and the condition can be treated at home. However, if there is any uncertainty or concern over the condition, or the symptoms are severe, seeing a doctor is very important. 6 Causes for concern include: 2 5 6
- Intense pain in the eye
- Extreme redness, especially in one eye only
- Inability to open the eye
- Severe sensitivity to light
- Discharge that contains a lot of pus
- Constant blurred vision, or difficulty seeing
A doctor will take the person’s medical history and ask whether anyone they know might have had an eye infection recently. They will examine the eyes and assess the signs and symptoms present, taking care to rule out allergic conjunctivitis, bacterial conjunctivitis, dry eye syndrome and other more serious eye conditions, such as uveitis and keratitis. 2
If the conjunctivitis seems severe or very long-lasting, the doctor may take a small sample of discharge from the eye and send it for laboratory tests to identify the cause and determine the most effective treatment approach. 2 7
Viral conjunctivitis treatment
Mild cases of viral conjunctivitis often clear up within roughly 1-3 weeks without special medical treatment. Symptoms may become worse before getting better.
A number of home remedies and over-the-counter treatments may help to relieve the discomfort caused by viral conjunctivitis: 2 6 1
- Applying a cold or warm compress; a clean cloth that has been soaked in water; to the eye
- Gently clean discharge from the eye with a clean cloth, sterile pad, or cotton wool soaked in water
- Applying lubricating eye drops to the eye; these are called artificial tears and are available without a prescription. Care must be taken not to use the drops in the other eye if only one eye is infected
- Applying antihistamine/decongestant eye drops, which are often available without a prescription; these may help to reduce irritation 5
- Avoiding the use of contact lenses until the infection has cleared
Generally, it is not considered necessary for a child with viral conjunctivitis to stay off school, unless an outbreak of multiple cases has occurred. However, a particular daycare center or school may have their own policy and ask that the child be kept at home until their symptoms have cleared up, to reduce the likelihood of infecting other children. 6
Antibiotics are not recommended for the treatment of viral conjunctivitis, as they are not effective against viruses, but bacteria. 6
Antiviral medication for viral conjunctivitis
Sometimes, topical or oral antiviral medication may be recommended. This is typically reserved for cases of viral conjunctivitis which: 6 1
- Are severe, such as those caused by the herpes simplex virus or varicella-zoster virus
- Are very long-lasting
- Occur in newborn babies
- Occur in people who have weakened immune systems
In epidemic keratoconjunctivitis and other serious types of viral conjunctivitis, steroid eye drops and other types of treatment may sometimes be necessary. 3 6 While steroid medication can be very effective, it can cause serious side-effects and complications and is generally only used short term.
Complications of viral conjunctivitis
Most mild cases of viral conjunctivitis clear up completely, without causing any complications. However, in a small number of severe cases, the infection can cause serious complications, including: 6
- Ulcers and inflammation of the cornea (keratitis)
- Scarring of the eye and damage to vision
If a person experiences any severe symptoms, or is concerned about an eye infection, it is advisable that they see a doctor immediately.
Viral conjunctivitis in babies
Newborn babies can be affected by various types of conjunctivitis, including viral conjunctivitis. Pink eye in infants is called neonatal conjunctivitis or ophthalmia neonatorum. Babies with conjunctivitis typically develop puffy, red eyelids and discharge from the eyes within 1-14 days of birth. 6 8
A baby’s eyes may become infected with a virus from the mother during the childbirth process, including the cold virus (adenovirus) and the viruses that cause oral and genital herpes; herpes simplex 1 and herpes simplex 2. 8 9
Viral and other types of conjunctivitis in babies can be very serious, and urgent medical attention is required. Viral conjunctivitis in an infant may need to be treated with antiviral medication, and referral to a specialist may be necessary. 9
Conjunctivitis in a baby is sometimes mistaken for sticky eyes caused by a blocked tear duct. However, a blocked tear duct will not cause the redness or swelling seen in conjunctivitis. 6
Prevention of viral conjunctivitis
While it may not always be possible to prevent viral conjunctivitis, taking the following steps can help to reduce the likelihood of an infection: 1 4 5
- Avoiding contact with people who have pink eye
- Maintaining good hygiene, such as washing your hands often with soap and water, or using hand sanitizer
- Avoiding touching your eyes when your hands are not clean
If you have viral conjunctivitis, the following actions can help avoid spreading the infection to others: 1 2 4 5
- Maintaining good hygiene, such as washing your hands often with soap and water, or using hand sanitizer, especially after treating the eyes
- Cleaning your spectacles
- Avoiding touching the eyes other than when treating them, as this can spread the virus
- Washing pillowcases and towels often and avoiding sharing them with others
- Avoiding sharing makeup and eyedrops
- When necessary, staying off school or work until symptoms of viral conjunctivitis have cleared; this is generally when the eyes are no longer red and irritated
- Avoiding the use of swimming pools
In addition, contact lenses should not be worn until symptoms have cleared, and a new pair used when the infection has gone away. Some makeup may also need to be discarded and replaced to prevent reinfection. 1 2
Other names for viral conjunctivitis
- Viral eye infection
- Pink eye, or pinkeye
Viral conjunctivitis FAQs
Q: How long is viral conjunctivitis contagious?
A: A person with viral conjunctivitis is usually contagious from the time symptoms begin appearing and for the duration of the illness, until it has cleared up. A general rule is that as long as the eyes are red, the virus may be spread. 10 Worried that you or a loved one may have symptoms of viral conjunctivitis? Get a free assessment with the Ada app.
Q: How is viral conjunctivitis spread?
A: Viral conjunctivitis is readily spread through direct contact, for example when a person with the condition touches their eyes and then touches an object, such as a door handle or another person’s hand. If that person then touches their eyes without washing or sanitizing their hands, they may develop viral conjunctivitis. Objects that are in contact with the eyes, e.g. towels or pillowcases, can also be contaminated easily. Viral conjunctivitis can also be spread through the sharing of eye drops, mascara, and other eye makeup, and via communal bathing, e.g. swimming pools, saunas, and hot tubs. 5 6
Q: Viral conjunctivitis vs. bacterial conjunctivitis – what is the difference?
A: While both types of conjunctivitis are highly contagious, the causes, some of the symptoms, and the treatments are different. Viral conjunctivitis is caused by a virus, often one of the groups that cause the common cold, results in a watery discharge from the eye and generally has no specific treatment. Bacterial conjunctivitis is caused by bacteria, results in a thick, sticky discharge from the eye, and may – in some cases – require antibiotic eye drops.
Q: Viral conjunctivitis vs. pink eye – what is the difference?
A: Pink eye is the common term for all types of conjunctivitis. Viral conjunctivitis is one type of pink eye, and refers to pink eye that is caused by a virus, e.g. from the group of viruses that cause the common cold. Other types of pink eye include bacterial conjunctivitis and allergic conjunctivitis.