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Viral vs Bacterial Pink Eye


Pinkeye is the common term for conjunctivitis. Conjunctivitis means inflammation of the membrane which covers the sclera (white of the eye) as well as the inside of the eyelids. The inflammation may be caused by infection, physical trauma, chemical irritation, or allergy. The significance and repercussions of conjunctivitis varies depending upon the age of the child.

Historically, during the newborn period there was much concern over the devastating effects of neonatal ophthalmia ( which was severe conjunctivitis caused mainly by Neisseria gonorrhea or Chlamydia trachomatis). The infection would be introduced into the eye during passage through the birth canal. Today, routine screening and treatment for these sexually transmitted diseases in pregnant women, as well as state-mandated application of erythromycin ointment in the eyes of all newborns, has markedly diminished this illness. While a good preventative against the N. gonorrhea, the erythromycin ointment, however, does not prevent chlamydial disease. And importantly, if your newborn has discharge from the eyes, the topical erythromycin is not adequate treatment against either chlamydial or ‘gonococcal’ conjunctivitis. Discharge from the eyes in the newborn period thus should be cultured by your child’s physician. Newborns with known blockage of the lacrimal ducts need not return for each episode of increased discharge if an alternative plan has been implemented by your child’s physician.

After the newborn period, the organisms responsible for conjunctivitis tend to be the same organisms which cause upper respiratory illnesses. Many are adenoviral and will not respond to antibiotics of any kind. Nevertheless, some are bacterial, and because cultures are usually not performed at this age, and given the tendency of infants and young children to introduce bacteria into the irritated eye from unclean hands, many physicians will prescribe antibiotics in all cases.

Viral and Bacterial Pinkeye Symptoms

Viral pinkeye tends to have a watery discharge, whereas bacterial pinkeye tends to have a thick, yellowish eye discharge. Daycare centers tend to be very sensitive to pinkeye. Most day cares require that a child with pinkeye be seen by their physician. If the diagnosis is viral pink eye, they can return to day care. If the diagnosis is bacterial pink eye, they can return to day care after 24 hours of topical eye antibiotics. All children with conjunctivitis should be seen by their healthcare provider for accurate diagnosis. It is important to note that approximately 20-30% will have an ear infection at the same time. If an ear infection is also present on physical examination, oral antibiotics will treat both the ear infection and the eye infection.

In older children, adolescents, and adults, the same is true as with the younger children, but, in addition, allergic conjunctivitis plays a larger role. Allergic conjunctivitis appears similar to viral conjunctivitis, with watery eye discharge. Allergies will also cause itching. Sports related conditions also begin to contribute which include: Chemical conjunctivitis from pool water and adenovirus infections from pool water; irritation from airborne sand, dust, rain and snow (in skiers/snowboarders); and irritation from inadequate sleep, poor hydration or marijuana use.

Rarely, redness of the sclera may not be conjunctivitis at all, but is related to glaucoma (high pressure in the eye), inflammatory conditions (juvenile rheumatoid arthritis, Kawasaki’s disease, Sicca syndrome, and many others), or blood vessel malformations around the eye. For these reasons, timely follow-up of any conjunctivitis which does not improve quickly, is essential.