In their ordinary locations the yaws tubercles are not painful unless pressed firmly but when located on the palms of the hands or soles of the feet the thick skin of these regions exerts pressure so that in such situations the lesions are painful.
In this stage yaws does not involve mucous membranes or affect the viscera.
The secondary stage lasts from 3 or 4 months to 2 or 3 years, the yaws tubercles coming out in successive crops in long standing cases.
The Tertiary Stage.—Daniels noted in the Fiji Islands destructive lesions of the naso-pharyngeal region which he thought might be associated with a preceding yaws attack. He noted cutaneous lesions which resembled lupus vulgaris. Boissiere has noted not only the nasopharyngeal lesions and lupus-vulgaris-like ones but also tibial involvement, joint swellings and dactylitis.
Numa Rat describes various tertiary manifestations. There may be subcutaneous nodules about ankle or leg which soften and may produce bone lesions and deformities. He notes destructive lesions of nares, pharynx and palate which may set in years after an attack of yaws. His description of the process starting as an ozoena or sore throat followed by destruction of the uvula, velum palati and septum nasi is much like gangosa. Howard has noted the greater frequency of destructive lesions of the nasopharynx in those parts of Africa where yaws is prevalent than in parts where syphilis prevails.
Fig. 123.—Tertiary jaws, “Gomma”. (Johns Hopkins Bull., Moss and Bigelow.)
According to Castellani the characteristic lesions of tertiary yaws are gummatous nodules and deep ulcerations. Such ulcerations may give rise to contractures.
In Guam the view now prevails that the condition known as gangosa is a form of tertiary yaws.