II. Epidemiology
- Viral Conjunctivitis is most common Conjunctivitis cause (80% of cases)
- Viral Conjunctivitis accounts for 55 to 80% of Conjunctivitis cases in adults
 - Bacterial Conjunctivitis is more common in children (up to 71% of cases)
 
 - Typically spread by contaminated hands
 - Viral sources can survive on fomites for up to 72 hours
 - Common cause of Swimming Pool Conjunctivitis (esp. Adenovirus)
- Chlorine does not eliminate Adenovirus
 
 
III. Causes
- 
                          Adenovirus (most common)
- Highly contagious (survives up to 28 days, 30% transmission rate)
 - Transmitted via fomites (e.g. fingers, cosmetics) and swimming pools
 
 - Epidemic Keratoconjunctivitis (more severe, Lymphadenopathy)
 - Enterovirus
 - Coxsackievirus
 - Varicella Zoster Virus (Herpes Ophthalmicus)
 - Epstein-Barr Virus (EBV, Mononucleosis)
 - Herpes Simplex Virus (Herpes Keratitis)
 - Influenza
 
IV. Symptoms
- Mild watery Eye Discharge or tearing
 - Insidious onset over 36 hours
 - Mild eye burning to no pain (eye may feel gritty)
 - Mild eye itch
 - Diffuse Conjunctival Hyperemia
 - Unilateral initially and spreads to opposite eye within 1-2 days
 - Associated symptoms
- Upper Respiratory Infection
 - Severe Pharyngitis with some infections (e.g. coxsackievirus, Mononucleosis)
 
 
V. Signs
- Marked Conjunctival erythema
 - Epiphora (Eye tearing)
 - 
                          Preauricular Lymphadenopathy (anterior to tragus)
- Highly suggestive of Viral Conjunctivitis (especially Adenovirus)
 
 - Mild palpebral Conjunctival follicular response
 - Multiple small subepithelial Corneal infiltrates (severe cases)
 - Fever
 
VI. Differential Diagnosis
VII. Precautions: Red Flags
- See Conjunctivitis
 - See Herpes Ophthalmicus
 
VIII. Management
- Conditions requiring urgent ophthalmology referral
 - Warm soaks to keep lids and lashes free of debris
 - Cool compresses may be soothing
 - Practice good hygiene to prevent contagious spread
- Hosts shed Adenovirus for 10 to 14 days
 - Avoid exposing others for at least 7 days, and at least until Red Eye and tearing resolves
 
 - Topical lubricant eye drops (Methylcellulose, Refresh Tears) or artificial tears
 - Remove Contact Lens and do not wear again until Conjunctivitis resolves
 - Avoid Topical Corticosteroids (prolonged viral shedding, Glaucoma risk)
 - 
                          Antibiotic not indicated in Viral Conjunctivitis
- See Bacterial Conjunctivitis
 - Risk of Antibiotic Resistance, transmission of Viral Conjunctivitis to contralateral eye, chemical Conjunctivitis
 
 
IX. Prevention
- Frequent Hand Washing
 - Do not share towels, pillowcases or eye makeup
 - Throw away used Contact Lenses and their case
 - Throw away used eye makeup
 - Avoid touching your face
 - Wipe contaminated surfaces with bleach
- Adenovirus survives on surfaces for 72 hours
 
 
X. Course
- Eye discomfort may persist for up to 10 days
 - Infectious while excessive eye watering continues (typically 10-14 days)
- Return if failed resolution by 2 to 3 weeks
 
 
XI. Resources (Include Patient Education)
XII. References
- Williams (2017) Crit Dec Emerg Med 31(2): 3-12
 - Cronau (2010) Am Fam Physician 81(2): 137-44 [PubMed]
 - Winters (2024) Am Fam Physician 110(2):134-44 [PubMed]