Conjunctivitis (Viral / Pink Eye)
Viral conjunctivitis is an acute, highly contagious inflammation of the bulbar and palpebral conjunctiva usually caused by adenoviruses and characterised by watery discharge, conjunctival hyperaemia, foreign-body sensation and, frequently, pre-auricular lymphadenopathy. It spreads rapidly through respiratory droplets, contaminated fingers, ophthalmic instruments, swimming-pool water and personal items, leading to epidemics in schools, workplaces and eye-care clinics. The illness is self-limited in healthy hosts, resolving within one to two weeks, yet its extreme transmissibility and the visual morbidity of epidemic keratoconjunctivitis make it a major public-health concern.
Symptoms
Patients typically develop acute onset of unilateral gritty foreign-body sensation, burning, excessive tearing, mildly pruritic red eye and eyelid edema that spreads to the fellow eye within 24–48 h. Clear to mucoserous discharge causes morning eyelash crusting but the lids separate easily. Associated findings include photophobia, blurred vision due to tear film debris, punctate keratitis and tender pre-auricular or submandibular lymphadenopathy. In epidemic keratoconjunctivitis, membrane or pseudomembrane formation, subepithelial corneal infiltrates and decreased visual acuity may appear after one week. Systemic symptoms of pharyngitis, low-grade fever or rhinitis suggest pharyngoconjunctival fever in children.
Risk Factors
Close contact with an infected individual, poor hand hygiene, sharing towels or cosmetics, crowded living conditions, swimming pools lacking adequate chlorination, contact-lens wear with inadequate disinfection, upper-respiratory-tract infection, ocular surface disease, immunosuppression and ocular procedures such as tonometry or LASIK increase acquisition risk.
Diagnosis
Diagnosis is clinical, based on watery discharge, follicular conjunctivitis and pre-auricular adenopathy without purulent exudate or glued eyelashes. Rapid adenoviral antigen immunoassays (AdenoPlus) offer 90 % specificity when uncertainty exists. PCR of conjunctival swabs confirms atypical cases or guides infection-control in outbreaks. Fluorescein staining rules out dendritic lesions of HSV keratitis. Cultures and Gram stain are reserved for severe purulence suggesting bacterial super-infection.
Treatment
No antiviral is approved for routine adenoviral conjunctivitis; management is supportive. Cold compresses, preservative-free artificial tears four to eight times daily and frequent gentle lid cleansing relieve irritation. Topical antihistamine–vasoconstrictor combinations (ketotifen, olopatadine) diminish itching and hyperaemia. For severe chemosis or membranes, short courses of topical corticosteroid (prednisolone acetate 0.125–1 % q.i.d. for 5–7 days then taper) hasten symptom relief but require ophthalmologic supervision to monitor IOP and prevent prolonged viral shedding. Topical povidone-iodine 0.4–1 % paired with dexamethasone, administered once in clinic, shortens viral load and clinical course in randomised trials, though not yet standard of care. Broad-spectrum topical antibiotics are unnecessary unless bacterial super-infection is suspected. Patients should avoid contact lenses until 24 h after resolution.
Outlook
Uncomplicated cases resolve within 7–14 days; keratitis and subepithelial infiltrates can blur vision and photophobia for weeks but usually fade over three months. Recurrence is rare but prolonged shedding (up to 14 days) facilitates household spread. Prompt infection-control measures limit outbreaks in clinics and schools.
Complications
Subepithelial corneal infiltrates causing prolonged glare and reduced acuity, membrane or pseudomembrane formation with symblepharon, secondary bacterial keratitis, dry-eye disease from goblet-cell loss, conjunctival scarring and very rarely Stevens–Johnson syndrome can complicate severe or mismanaged viral conjunctivitis.
Prevention
Rigorous hand hygiene, single-use instruments in eye clinics, high-level disinfection of tonometer tips, slit-lamp chin-rest covers, exclusion of symptomatic children from daycare, chlorination of pools to 1–3 ppm free chlorine, quarantine of infected athletes from contact sports and vaccination against measles, VZV and SARS-CoV-2 mitigate viral conjunctivitis incidence. Development of recombinant adenovirus vaccines is ongoing.
Support
Wash hands with soap for ≥ 20 s after touching eyes, use 60 – 95 % alcohol-based sanitiser when sinks are unavailable, avoid eye rubbing, use separate towels, pillowcases, cosmetics and contact-lens accessories, disinfect phone screens and computer keyboards daily, and remain off work, school or swimming pools until discharge subsides (usually 5–7 days). Disposable cold compresses and single-use tears reduce fomite transmission. Caregivers should wear gloves for medication instillation and launder linens in hot water.
Sources
The information presented above is supported by reputable medical sources and research publications. These references provide additional clinical insights and evidence-based findings for healthcare professionals and individuals seeking comprehensive understanding of this medical condition.
