The conjunctiva is a vascularized mucous membrane that covers the anterior surface of the globe, fornical conjunctiva and the posterior surface of the upper and lower eye lids. Conjunctivitis refers to any inflammatory condition of this membrane. The common cause of conjunctivitis is infection by bacteria or viruses; also it can be caused by chemical irritants, traditional eye remedies or allergy. Usually it is a self-limiting condition, but it may be extremely contagious. It may easily spread in day care centres and school class rooms leading to absences or lost time from work for parents. The general recommendation is that a patient with eye infection should not attend work neither school until the infection clears. Sometimes infection of the conjunctiva may invade the cornea and can cause perforation e.g. gonococcal infection.
Acute infectious conjunctivitis is a common disorder with annual incidence of 1.5-2% in primary care centres. In children incidence of acute infectious conjunctivitis is higher than in adults and the spectrum of causative micro-organisms may differ from that in adults. The most common aetiology of infective conjunctivitis in children is bacteria and this is responsible for 54-74% of all cases of infective conjunctivitis. The common clinical presentation is red eye. Purulence, swollen eyelids and a papillary response are generally associated with bacterial aetiology, while watery discharge, a follicular response and preauricular node are more indicative of viral picture.