Venereal diseases (Sexually Transmitted Diseases) commonly seen in enlisted men - often mistakenly diagnosed as syphilis
While the treatments for all venereal diseases were pretty horrible back in the day (except for herpes - they at least realized that they couldn’t do anything for it, in most practices), the “treatment” for syphilis was usually far worse than the others.
Mercury was taken orally in various compounds, and was rubbed into the open sores. Arseno-benzene (an active compound to deliver arsenic) was often injected directly into the penis, and taken orally (for both men and women).
Complicating things, many venereal and other contagious diseases can mimic the symptoms of primary syphilis. Two of these three men did not have syphilis, but had been initially diagnosed and treated for it. The third actually had syphilis, but was initially treated for scabies.
Top left: Syphlitic leucoderma (“white skin”) of the penis - Initially diagnosed as scabies.
Top right: Long-standing scabies infection, where the sores mimicked syphilitic chancres (patient also has gonorrhea)
Bottom: Herpes genitalia of the penis. Diagnosed by untrained physician as syphilis. Not commonly confused with other conditions.
Venereal Disease: Their Clinical Aspect and Treatment. J. E. R. McDonagh, 1921.