Yaws, or frambesia, is essentially a tropical infectious and contagious disease caused by Spirochaeta pertenuis and characterized by a frambesiform granulomatous eruption.
Our knowledge of yaws is due to the following investigators: Charlouis,1 who in 1881 proved by actual experiment that syphilis and yaws are two distinct maladies. This investigator inoculated thirty-two Chinese prisoners with crusts and scrapings from yaws lesions, and in twenty-eight instances succeeded in producing characteristic yaws. He also succeeded in inoculating a native suffering from yaws with syphilis, thereby definitely disproving the assumption that the two conditions were one and the same. It is a further matter of established fact that a syphilitic patient may contract yaws in the usual manner, as well as experimentally. For our clinical knowledge of yaws, we owe much to Numa Rat2 and more recently to Castellani.3 Rat's report, published in 1891, has become classic. The most important