There are numerous diseases that can cause follicular eruptions. Follicular keratoses caused by genetic disorders or inadequate nutrient intake, for example, are generally not contagious. However, follicular keratosis caused by infectious follicular keratosis may cause contact transmission. Infectious follicular keratosis, also known as acne vulgaris (Brooke’s disease), is most commonly seen in children. The lesions are symmetrical and widespread, mainly on the neck, shoulders and extremities, and appear as keratotic patches, especially on the hair follicles, with black keratotic plugs, sometimes accompanied by mild systemic symptoms, which may resolve spontaneously within 1 to 2 months.