The late latency period begins somewhat arbitrarily 1-4 years after the symptoms disappear. The late stage of latency can continue indefinitely. It has been found that fifty to seventy percent of patients in this stage live out the rest of their lives without the disease progressing to the infamous tertiary phase. Tertiary syphilis is one of the most dreaded diseases a person can suffer. At this stage, the individual is no longer infectious but is in great danger of losing his or her own life to the disease.
Lesions develop on the skin, bone, and vital organs.
On any part of the body, the spirochetes can concentrate and form painful lesions or gummas. Gummas are ugly and painful tumors that result from the T. pallidum concentrating on a small area of body tissue. The bones of the individual also get eaten away in a way that is similar to osteomyelitis. There are two particular kinds of tertiary syphilis, named for where the spirochetes do the most damage. One is cardiovascular syphilis in which the bacteria concentrate on the aorta and cause the valves to degenerate.