Human Adenovirus Conjunctivitis (Adenoviral Conjunctivitis)

"Overview"

- **Human adenovirus (HAdV)** is a highly contagious virus that affects all mucosal tissues, including the ocular surface, and is considered the most common cause of infectious conjunctivitis (red eye) worldwide.

- **Transmission** occurs via hand-to-eye contact, particularly in closed environments such as schools and hospitals, which can lead to outbreaks.

- The **most common and severe ocular manifestation** is epidemic keratoconjunctivitis (EKC), usually caused by group D adenoviruses (types 8, 19, and 37).

- The disease typically starts in one eye and, after several days, may involve the other eye in a milder form.

- **Key symptoms**: Excessive tearing, foreign body sensation, itching, pain, and light sensitivity (photophobia).

- **Distinct complications**: Persistent corneal opacities (nummular opacities), blurred vision, and glare, which can last for months or even years.

- The eye's **immune response** to the virus includes secretion of cytokines such as IL-8 and other inflammatory proteins, which can influence disease severity.

Clinical Features:

- **Patients suddenly experience a foreign body sensation in the eye.**

- **The affected eye becomes red, with more prominent superficial vessels.**

- **Patients report burning and itching.**

- **Watery or mucoid discharge increases (watery discharge is typical).**

- **Patients develop photophobia (light sensitivity).**

- **Follicular reactions on the conjunctiva are common.**

- **The examiner may observe conjunctival swelling (chemosis) and edema.**

- **Preauricular lymphadenopathy is common; the lymph node is usually tender.**

- **A membrane or pseudomembrane may be seen on the palpebral surface.**

- **In severe cases, decreased vision and subepithelial corneal infiltrates may be found.**

- **Patients often report a recent upper respiratory tract infection or close contact with an affected person.**

*(Reference: StatPearls, Viral Conjunctivitis, 2024)*

### Treatment of Adenoviral Conjunctivitis

1. **Supportive/Symptomatic Management** 

   - Use artificial tears (4–10 times/day, preferably preservative-free) for dryness and irritation.

   - Cold compresses reduce inflammation and discomfort.

   - Avoid use of contact lenses until complete recovery.

   - Advise frequent handwashing, avoidance of touching the eyes, and abstention from sharing personal items (towels, bedding).

2. **Prevention of Transmission** 

   - Strict attention to personal hygiene is essential.

   - Patients should be isolated and avoid attending work or school until symptoms resolve.

3. **In Special Cases** 

   - Removal of membrane/pseudomembrane at the slit lamp under topical anesthesia to prevent scarring, if present.

   - Topical corticosteroids: Only in severe cases with vision loss from subepithelial infiltrates or significant photophobia, and strictly under ophthalmologist supervision, as steroids may prolong viral shedding.

   - Topical antibiotics are **not recommended** unless needed for prevention or treatment of bacterial superinfection.

*(Reference: O’Brien TP, Jeng BH. Viral Conjunctivitis. StatPearls [Internet]. 2024. “Treatment / Management”)*

### Prognosis

- **Most cases resolve spontaneously and without complications.**

- **Typical recovery is 14–30 days (2–4 weeks).**

- Rarely, chronic infection or complications such as punctate keratitis, bacterial superinfection, conjunctival scarring, and corneal ulceration can occur.

- Some patients may experience prolonged photophobia, reduced vision, or glare.

- Severe complications are rare but warrant ophthalmological follow-up.

### Patient Education

- **Emphasize high contagion:** Patients should be informed that the infection is highly contagious and strict hand hygiene, avoidance of touching the eyes, and not sharing towels or personal effects are vital.

- **Isolation:** Patients should refrain from work, school, or public places until symptoms resolve completely.

- **No contact lens use:** All patients, especially children, should avoid wearing contact lenses until fully asymptomatic.

- **Educate parents, teachers, and healthcare teams:** Raise awareness about transmission and the importance of isolating cases in schools and communal settings.

- **Healthcare settings:** Hospitals and clinics should examine patients with suspected conjunctivitis in separate rooms. Proper signage and staff precautions (like frequent handwashing and minimizing physical contact) are critical.

- **Follow-up:** Advise revisit if symptoms persist beyond 4 weeks, or in case of visual decline or pain.

Reference:

- O’Brien TP, Jeng BH. Viral Conjunctivitis. StatPearls [Internet]. StatPearls Publishing; 2024 Jan–. 

[https://www.ncbi.nlm.nih.gov/books/NBK470271/ (https://www.ncbi.nlm.nih.gov/books/NBK470271/).**