Epidemic Keratoconjunctivitis (EKC)

A Highly Contagious Viral Eye Infection

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Epidemic Keratoconjunctivitis (EKC) is a contagious eye infection, often referred to as viral conjunctivitis. EKC is an inflammation of the cornea and conjunctiva. (In pink eye or conjunctivitis, only the conjunctiva is inflamed.) It is highly contagious and can last as long as a month. EKC occurs mostly in places of close human contact, such as schools, hospitals, and office environments.

Cause of Epidemic Keratoconjunctivitis

EKC is caused by a virus called adenovirus.

Adenovirus also causes similar conditions such as pharyngoconjunctival fever. Although some research shows that it may be transmitted by air droplets and swimming pools, the most common way it develops is by direct contact with tears or other fluids from infected eyes. Eye doctors are well educated about EKC because, unfortunately, an eye doctor’s office can be one of the most common places to come in contact with adenovirus. Many outbreaks can be traced back to improperly disinfected diagnostic instruments.


People with EKC usually complain of a sudden onset of eye redness, irritation, soreness, light sensitivity and excessive tearing. Some people with the infection say that it feels like a piece of sand or foreign body is in the eye. Both the eye and eyelid can become swollen, red and irritated. The viral infection usually involves one eye first, then eventually infects the other eye.

People with EKC may have significantly blurred vision for several days. Symptoms usually last for about two weeks.

Diagnosis of Epidemic Keratoconjunctivitis

Doctors diagnose EKC by listening closely to a patient’s complaints and eye health history. The infection is usually recognizable by eye doctors -- a patient will often complain of infectious symptoms and then several days later develop subepithelial infiltrates.

A subepithelial infiltrate can appear as a whitish area on the cornea that can temporally reduce vision. Some people may also have swollen lymph nodes in front of the ears. Doctors use a microscope called a biomicroscopic slit lamp to examine the front part of the eye. Patients sometimes develop a mucus-type membrane called a pseudomembrane on the tissue under the lower eyelid on the conjunctiva. Although the diagnosis is often made by examining the patient, doctors now have a new test that produces an accurate diagnosis of adenovirus. This test is called the RPS Adeno Detector and can deliver accurate diagnostic results in 10 minutes. This is an important development in eye care because antibiotics, which are not effective for treating EKC, are often over-prescribed for this condition.

Treatment of Epidemic Keratoconjunctivitis

Since antibiotic medicines are not effective in treating EKC, treatment focuses on alleviating unwanted symptoms. In mild cases, doctors prescribe cold compresses, artificial tears, and vasoconstrictors. In more severe cases, steroid eye drops are prescribed and are tapered over 2 to 4 weeks or longer. If pseudomembranes develop, doctors may remove them depending on severity.

Some doctors feel that decreasing the amount of virus present on the eye instantly will vastly shorten the course of the illness and make the patient feel better quickly. Betadine,(povidone-iodine) a common disinfectant used by doctors and hospitals to sterilize a part of the body before a procedure, is used for this purpose. However, the application must be done very carefully as it can stain the eye tissues. A company called Foresight Biotherapeutics is developing a commercially prepared medication that contains 0.4% povidone-iodine and dexamethasone, a steroid to treat EKC.v Biomedical companies are also investigating the treatment of EKC with cidofovir, an antiviral drug.

Research for the treatment of EKC is ongoing.

A Word From VeryWell

Epidemic keratoconjunctivitis (EKC) is a highly contagious infection of the front part of the eye. The miserable infection can be easily spread by coming into contact with the tears or discharge from the eyes of an infected person. A person could catch the infection by touching a contaminated surfaces or object and hen touching their own eyes. Symptoms can be quite bothersome, including redness, itching, irritation and tearing but usually resolve in about two weeks. If you develop EKC, it is important to practice good hygiene (frequent hand washing) to avoid spreading the infection to other people. 


EyeWiki, "Epidemic Keratoconunctivitis. American Academy of Ophthalmology, 27 April 2016.