There has always been considerable interest in the tropical disease known as yaws or frambŒsia tropica, not only for itself, but also on account of its resemblance to syphilis, and one group of English physicians, headed by Mr. Hutchinson,1 has even gone so far as to say that if "yaws be not syphilis it is very clear that it offers a very exact parallel to it." The physicians of Mr. Hutchinson's school have tried to clear up the question of the origin of syphilis by suggesting that it is an evolutionary form of yaw.2 All authorities unite in agreeing that the two diseases have many points of resemblance and that their relationship to one another is a most intimate one.
When the spirochete of yaws was first described by Castellani3 in June, 1905, his announcement aroused great interest among the students of syphilis as well as among the students
FREDERICK F. RUSSELL. THE COMPARATIVE MORPHOLOGY OF THE SPIROCHETES OF SYPHILIS AND YAWS (FRAMBŒSIA TROPICA).. Arch Intern Med (Chic). 1908;II(1):74–76. doi:10.1001/archinte.1908.00050060079005