The differential diagnosis of SARS-CoV-2 conjunctivitis includes other viral conjunctivitis such as adenoviral conjunctivitis, based on our findings (Table 5). 54.29% of conjunctivitis were completely unilateral, unlike adenoviral conjunctivitis where there is a greater tendency to bilateralization [11]. However, bilateral conjunctivitis in COVID-19 has also been described [3].
Table 5 Differential diagnosis between conjunctivitis in COVID-19 patients and adenoviral conjunctivitis
Conjunctivitis in COVID-19 Adenoviral conjunctivitis
Onset Abrupt Abrupt
Unilateral/bilateral Unilateral ++
Bilateral + Unilateral or bilateral (often sequentially bilateral)
Conjunctival injection Mild or very mild Varies in severity
Follicular reaction + +
Chemosis ± ±
Eyelid swelling and erythema – ±
Conjunctival petechiae /subconjunctival hemorrhage – ±
Discharge + ++
Epithelial punctate keratitis – ±
Corneal infiltrates – ±
Membrane/pseudomembrane formation – ±
Concurrent upper respiratory tract infection ± ±
Symptoms Very mild-mild Mild-severe
Natural history Self-limited within 2–4 days Self-limited within 5–14 days (could get worse during the first days)
Potential sequelae Not Known Severe cases: conjunctival scarring, symblepharon, subepithelial corneal infiltrates, decreased vision