Conjunctivitis is one of the most common eye diseases. Its name is descriptive, because the condition involves inflammation of the conjunctiva - a transparent connective tissue layer covering the white of the eye. Any inflammatory response therefore, which naturally includes vascular dilation and engorgement, will give the eye a red appearance.

Bacterial Conjunctivitis
Acute onset of redness, grittiness, itching, swelling of lids, mucupurulent discharge, beefy red conjunctiva and crusted eyelids stuck together on waking. More common in children. Causative organisms are staph. aureus, epidermidis, strep. Pneumonia.

Viral Conjunctivitis
Acute onset of watery discharge, redness, discomfort and photophobia. Bilateral in about 60% of cases, typically one eye preceding the other by few days. More common in adults. Follicles can develop on the undersides of the lids.

Herpes (simplex & zoster) & Chlamydia
conjunctivitis. The later is the most common cause of neonatal conjunctivitis. It is noteworthy that conjuntival reaction in neonates is papillary & not follicular because infants cannot form follicles until about the third month of life.