Epidemic keratoconjunctivitis (EK), defined as a highly contagious infection of the eye surface (the conjunctiva and associated tissues), is caused by double-stranded DNA adenoviruses [1] [2]. More than 50 adenoviruses have been described in the literature, but serotypes 8, 19, and 37 are established as main pathogens of EK [2] [3] [4]. Because of their resistance to the majority of disinfectants and heat tolerance (they are able to survive at room temperature), adenoviruses are potent causes of epidemic infections and outbreaks, one of them being epidemic keratoconjunctivitis [3]. Humans are the only known reservoir of adenoviruses, and person-to-person transmission is achieved through direct or close contact with individuals (mainly tear fluids) who are actively shedding the virus when exhibiting signs and symptoms, while some studies have established that individuals remain infectious even a few weeks after resolution of symptoms [1] [2] [3]. After an incubation period that lasts for about 2-12 days, the clinical presentation is distinguished by a severe inflammatory process that leads to redness of the eye accompanied by irritation, excessive tearing and discharge that causes blurred vision, as well as photophobia and a sensation of foreign body presence [2] [3] [5] [6]. EK initially affects only one eye, but it may spread to the other eye as well, although with a much milder presentation [2]. In some patients, generalized symptoms in the form of fever, headaches, proximal lymphadenopathy appear (preauricular lymph nodes are most often involved), but the prognosis is generally self-limiting [2] [3] [5]. EK is predominantly reported in crowded areas (eg. schools, health-care institutions, but also pools due to poorly chlorinated water that contains adenovirus particles) and has no seasonal predilection [2] [6].

The differential diagnosis of eye redness and conjunctivitis is quite broad, but despite the fact that adenoviruses are one of the most important causes of this clinical entity, a thorough clinical investigation is recommended in order to raise suspicion toward an adenovirus infection [5]. Key information may be obtained during history taking when the physician should inquire whether similar symptoms have been reported by other individuals who were in close contact with the patient (eg. classmates, coworkers). Physical examination is an equally important part of the workup, during which eyelid and periorbital edema are observed, in addition to conjunctival hyperemia [2] [3] [5]. A slit-lamp examination performed by a skilled ophthalmologist can further support the diagnosis by detecting conjunctival swelling, hyperemia, and pseudomembrane formation in some cases [2]. When sufficient clinical criteria are obtained, microbiological studies need to be employed. Viral cultures carry a very successful rate of detecting viruses from patient samples, but their rather long turnaround times often requires the use of alternative methods, such as antigen detection through serology and indirect immunofluorescence [5]. But the low specificity and sensitivity of these studies (together with cultures) have placed them in an inferior position compared to newer and faster, but equally sensitive and specific methods [2]. Polymerase chain reaction (PCR), a molecular test that can yield conclusive results within a day, is widely recommended as the main method of diagnosing adenoviruses, although its cost still reduces its overall use in general practice [2] [5] [7] [8].

There is no specific antiviral treatment for EKC. Management focuses on relieving symptoms and preventing the spread of infection. Patients are often advised to use artificial tears to soothe irritation and cold compresses to reduce swelling. In severe cases, topical corticosteroids may be prescribed to reduce inflammation. It is crucial to maintain good hygiene, such as frequent hand washing, to prevent transmission.

The prognosis for EKC is generally good, with most patients recovering fully within two to three weeks. However, some individuals may experience lingering symptoms, such as blurred vision or corneal opacities, which can persist for several months. These complications are rare and usually resolve over time.

EKC is caused by adenoviruses, a group of viruses that can infect the respiratory tract, eyes, and other body systems. The specific adenovirus serotypes associated with EKC include types 8, 19, and 37. These viruses are highly contagious and can spread through direct contact with infected individuals or contaminated surfaces.

EKC occurs worldwide and can affect individuals of all ages. Outbreaks are more common in densely populated areas and can occur in settings such as schools, hospitals, and military barracks. The infection is more prevalent in the summer and fall months, although it can occur year-round.

The pathophysiology of EKC involves the invasion of adenoviruses into the epithelial cells of the conjunctiva and cornea. This leads to an inflammatory response, causing the characteristic symptoms of redness, swelling, and discomfort. The immune response to the virus can also result in the formation of subepithelial infiltrates, which may cause temporary vision changes.

Preventing the spread of EKC involves practicing good hygiene. Individuals should avoid touching their eyes with unwashed hands and should not share personal items like towels or eye makeup. In healthcare settings, strict infection control measures, such as using disposable gloves and disinfecting surfaces, are essential to prevent outbreaks.

Epidemic Keratoconjunctivitis is a contagious eye infection caused by adenoviruses, characterized by redness, tearing, and discomfort. While there is no specific treatment, symptoms can be managed with supportive care. Good hygiene practices are crucial in preventing the spread of the virus. Most patients recover fully, although some may experience prolonged symptoms.

If you suspect you have EKC, it is important to avoid spreading the infection to others. Wash your hands frequently, avoid touching your eyes, and refrain from sharing personal items. Use artificial tears to alleviate discomfort and apply cold compresses to reduce swelling. If symptoms persist or worsen, consult an eye specialist for further evaluation and management.

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