Epidemiology Most cases of pityriasis rosea occur in young healthy persons, the majority of whom are between the ages of 10 and 35 years Its peak incidence is during adolescence, and it is rarely diagnosed before the age of 2 years. There is no racial predilection and it is found worldwide There is a slight female predominance, and some studies have even suggested a female: male ratio of 2: 1. The typical eruption lasts 6 to 8 weeks, though exceptionally it can persist for 5 months or longer Some authors report a modest seasonal variation with peaks in the spring and fallEpidemiology Most cases of pityriasis rosea occur in young healthy persons, the majority of whom are between the ages of 10 and 35 years. Its peak incidence is during adolescence, and it is rarely diagnosed before the age of 2 years. There is no racial predilection and it is found worldwide. There is a slight female predominance, and some studies have even suggested a female : male ratio of 2 : 1. The typical eruption lasts 6 to 8 weeks, though exceptionally it can persist for 5 months or longer. Some authors report a modest seasonal variation with peaks in the spring and fall