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].

• Fever

  Redness of the eye, as well as photophobia, blurred vision, ocular discharge, and in some cases, constitutional symptoms such as fever and lymphadenopathy, are described as main complaints. [symptoma.com]

  EKC patients may complain about influenza-like symptoms, including fever, malaise, respiratory symptoms, nausea, vomiting, diarrhea, and myalgia. [genome.jp]

  Symptoms: Foreign body sensation, photophobia, conjunctival hyperemic, eyelid stuck together in the morning, eyelid edema and sero-fibrinous discharge Ocular symptoms commonly preceded by systemic symptoms of fever, sore throat and sometimes gastrointestinal [dro.hs.columbia.edu]

  Family of adenoviruses contain different serotypes that can also cause pharyngoconjunctival fever, non-specific sporadic follicular conjunctivitis and chronic papillary conjunctivitis. [aimu.us]

  Occasionally, people may also get: fever headache extreme tiredness swollen lymph nodes. How is it spread? Epidemic keratoconjunctivitis is highly contagious and adenoviruses can live on surfaces for up to 30 days. [health.nsw.gov.au]

• Constitutional Symptom

  Redness of the eye, as well as photophobia, blurred vision, ocular discharge, and in some cases, constitutional symptoms such as fever and lymphadenopathy, are described as main complaints. [symptoma.com]

• Military Personnel

  PERSONNEL 46 TRAINING FOR MILITARY SPECIALTIES INCLUDING OPTIMAL CONDI 48 Sources arranged by dominions and countries 126 Abbreviations 129 MINUTES OF COMMITTEES 131 ANATOMY AND OPHTHALMOLOGY 135 Visibility as a function of wavelength 136 B Visual purple [books.google.com]

• Sputum

  She had a common cold with cough and sputum a week earlier followed by red eyes and watery discharge. Some of her kindergarten schoolmates also had red eyes during the same period. [dovepress.com]

• Gagging

  Adenovirus-specific polymerase chain reaction To demonstrate the presence of Ad, PCR was performed using the modified primers ADRJC1 5′-GAC ATG ACT TTC GAG GTC GAT CCC ATG GA-3′ and ADRJC2 5′-CCG GCT GAG AAG GGT GTG CGC AGG TA-3 '. [molvis.org]

• Conjunctival Injection

  RESULTS: After a mean of 1.8 0.7 days of oral steroid treatment, eyelid edema, corneal damage, conjunctival injection, follicles, and chemosis improved in all patients. [ncbi.nlm.nih.gov]

  Case Presentation A 67-year-old man was referred to Oculoplastics after suffering from conjunctival injection and chemosis in the right eye for 4 days. [karger.com]

  The hazard for resolution of lid edema (HR 0.41, adj.p 0.009), bulbar conjunctival injection (HR 0.55, adj.p 0.009), abnormal tear meniscus (HR 0.56, p 0.007), tearing (HR 0.54, adj p [digital.lib.washington.edu]

  Conjunctival injection and follicular reaction were found. There was also an enlarged tender pre-auricular lymph node on the right side. [dovepress.com]

  The right eye had a 1 conjunctival injection compared with her left eye’s 3 conjunctival injections of multiple petechial hemorrhages. There was a bilateral inferior palpebral folliculitis. Visual acuity measured 6/6 OD and 6/7.5 OS. [webmedcentral.com]

• Excessive Tearing

  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 [symptoma.com]

  tearing Follicular reaction Foreign body sensation This disorder is caused by a small virus and therefore has no specific treatment. [flei.com]

  Other classic features are burning, foreign body sensation, excessive tearing, and photophobia. [amboss.com]

  tearing) (Fig. 1-2) Foreign body sensation Blurred vision/loss of visual acuity Eyelid swelling Follicular reaction (Fig. 5 and 6) Clear or yellow discharge from the eye(s) Epithelial keratitis Systemic signs/symptoms: Lymphadenopathy (swollen nymph [eyewiki.aao.org]

  During the first five days of active disease there is pain/discomfort, redness of the white part of the eye and excessive tearing (watery/serous discharge from the eyes). [mastereyeassociates.com]

• Unilateral Red Eye

  Herpes Simplex Keratitis Signs and Symptoms The keratitis caused by the herpes simplex virus (HSV) typically presents as a unilateral "red eye" with a variable degree of pain or ocular irritation. [medicalstudy.blogspot.com]

• Fear

  Before these control measures were implemented, clinic personnel had followed the manufacturer's recommendations and disinfected pneumotonometer tips with 70% isopropyl alcohol, fearing that other disinfectants would corrode the instrument metal. [ncbi.nlm.nih.gov]

  Although corticosteroids may be used without fear in cases of herpes zoster (HZO) blepharitis, their use in cases of HSV infection may predispose the patient to the eruption of a dendritic keratitis. [medicalstudy.blogspot.com]

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].

1. Kimura R, Migita H, Kadonosono K, Uchio E. Is it possible to detect the presence of adenovirus in conjunctiva before the onset of conjunctivitis? Acta Ophthalmol. 2009 Feb;87(1):44-47.
2. Meyer-Rüsenberg B, Loderstädt U, Richard G, Kaulfers P-M, Gesser C. Epidemic Keratoconjunctivitis: The Current Situation and Recommendations for Prevention and Treatment. Dtsch Arztebl Int. 2011;108(27):475-480.
3. Viney KA, Kehoe PJ, Doyle B, et al. An outbreak of epidemic keratoconjunctivitis in a regional ophthalmology clinic in New South Wales. Epidemiol Infect. 2008;136(9):1197-1206.
4. Lee Y-C, Chen N, Huang I-T, et al. Human adenovirus type 8 epidemic keratoconjunctivitis with large corneal epithelial full-layer detachment: an endemic outbreak with uncommon manifestations. Clin Ophthalmol. 2015;9:953-957.
5. Pihos MA. Epidemic keratoconjunctivitis: A review of current concepts in management. J Optom. 2013;6(2):69-74.
6. Melendez CP, Florentino MM, Martinez IL, Mejia Lopez H. Outbreak of epidemic keratoconjunctivitis caused by adenovirus in medical residents. Mol Vis. 2009;15:557-562.
7. Adhikary AK, Numaga J, Kaburaki T, et al. Rapid detection and typing of oculopathogenic strain of subgenus D adenoviruses by fiber-based PCR and restriction enzyme analysis. Invest Ophthalmol Vis Sci. 2001;42:2010–2015.
8. Elnifro EM, Cooper RJ, Klapper PE, Yeo AC, Tullo AB. Multiplex polymerase chain reaction for diagnosis of viral and chlamydial keratoconjunctivitis. Invest Ophthalmol Vis Sci. 2000;41:1818–22