Heck's disease (focal epithelial hyperplasia): a longitudinal study.

A 3-year longitudinal study on Heck's disease among school children was undertaken in 2 communities which are similar geographically, socioeconomically and ethnically. The variations in the annual prevalence rates (7% to 13%), the incidence rates per 1000 (38 to 68), the female to male ratios (1:0.4 to 1:1) and the average ages of the affected pupils did not differ between communities and from year to year. Lesions varied in number, size and duration. Some were seen only at one of the examinations, while others remained during the whole study. The majority were situated on the mucosae of the lower lips and cheeks. The prevalence of lesions amongst school children in these two communities was noticeably higher than that of another community of similar ethnicity studied earlier. The clinical behaviour of the lesions is in keeping with what is expected of some HPV infections. The relatively high prevalence rate and the anatomical distribution of the lesions indicate the infectious nature of the disease, which we believe is influenced to a large extent by the lifestyle in these communities.