Jacyk W K
Int J Dermatol. 1980 Sep;19(7):397-9. doi: 10.1111/j.1365-4362.1980.tb03738.x.
One hundred thirty-eight Nigerian patients with pityriasis rosea were studied. Patients with the condition constituting 2.4% of all patients seen in two skin clinics in Northern Nigeria in a period of over three years. The proportional rate of pityriasis rosea parallels figures from other African studies, and is higher than values obtained in European series. Pyriasis rosea in Nigerians appears to be more florid and has a greater tendency to overstep the classic boundaries of distribution on the body, to affect the face and involve the oral cavity. The sex and age distribution was similar to European series, although some lowering of the age of onset of the condition was observed. No relationship between the frequency of pityriasis rosea and season was found.