**2. Epidemiology**

The estimated incidence of pemphigus is 1-16 cases per year per million people [1],[2]. PV is the most common type of pemphigus found in the USA and Europe. In the USA, PV is 5 times as prevalent as PF [3]. In contrast, PF is more common in certain countries such as Finland and South Africa [4] and the endemic variety, Fogo Salvegem, affects up to 3% of the population, in affected rural regions in Brazil, Columbia, and Tunisia [5]-[7].
