Because AOE is more likely to occur among swimmers and in warm, humid environments, it is not surprising that AOE peaks in the summer months (more than 44% of visits for AOE occur from June through August). Also, rates of AOE are higher in the humid Southeast (9.1/1,000 population), compared with other regions of the United States (see map). With increasing use of indoor recreational water facilities, however, it is not surprising to encounter AOE year round.

AOE is found among patients of all ages. The highest rates occur in 5- to 9-year-olds, but more than half of cases occur among adults (see table, p. 27). Once diagnosed with AOE, approximately 3.6% of ambulatory care patients are referred to another provider for additional care, and approximately 2.7% of all patients seen in the emergency department with AOE are admitted to the hospital.

Recent systematic reviews of treatment options for AOE have determined that topical treatment is highly effective.^16-18 Topical antimicrobials either alone or in combination with a corticosteroid are superior to placebo; cure rates are comparable between topical combination drops and topical antimicrobials alone.17 More research is needed to determine if topical corticosteroids alone are effective.¹⁶