• Morphologically identical, cannot be distinguished by any known test
• All have similar effects, differing in degree and range of affected tissues
• May be genetically distinct, lack cross-immunity (so have antigenic differences)
  

• TRANSMISSION: skin and mucous membrane contact or sharing eating utensils
• DISTRIBUTION: Closely related to poverty and isolation from organized social and health services (predominant in underprivileged remote rural communities)
• Unlike venereal syphilis, central nervous system involvement and congenital transmission do not occur in the endemic infections, usually limited to skin, bone, cartilage, and mucosae
  
• Usually affect children under 15 years

This explanation proposes that syphilis was present in Europe before Columbus' voyage, but was not identified as a separate disease from leprosy before the 1490s.  According to this theory, populations were small, and treponemal infection was mild and chronic. Larger population sizes selected for more acute infections, and the types of treponemes that depended on direct skin contact were outcompeted by the hardier, sexually transmitted strain.  Thus, the origin of venereal syphilis resulted from social and economic events, and not directly related to the return of Columbus from the New World. Proponents of this theory point to the ancient and medieval sources showing Pre-Columbian treponema infections in Europe.



One hypothesis argues for a New World origin, and holds that sailors who accompanied Columbus and other explorers brought the disease back to Europe in 1493. These researchers believe that syphilis originated in the New World due to a mutation in the bacteria that causes yaws (Rothschild, 2000). Based on a study of 1,000 skeletons from Africa, the Middle East, Europe, and Asia, Rothschild found no evidence of pre-Columbian Old World syphilis. According to his theory, Columbus' crew contracted syphilis in the New World and spread it through Europe.  The following syphilis endemic of 1500 suggested that the European population was previously unexposed to the disease which rapidly spread once introduced. Furthermore, the Rothschilds found that the earliest yaws cases in the New World collections were at least 6,000 years old, while the first syphilis cases were 800-1,600 years old. This suggests that syphilis may be a New World mutation of yaws, which has a worldwide distribution.  The discovery of treponemal antigens in the remains of a Pleistocene bear in the Americas, as well as an abundance of skeletal material with lesions that suggest treponemal agents, lend strong support for the presence of the disease in the New World pre-1492.

Treponema agent was present in the New World and the Old World at the time of Columbus' voyage, and has evolved along with human populations. This theory assumes that the treponematoses may have come down from a nonhuman primate ancestor, and the infections have exisited in man and his primate ancestors for millions of years (Cockburn, 1977).  According to this theory, each of the above mentioned trepanematoses are just manifestations of one single disease occuring with different social and environmental factors.
In the hot, humid climate of Sub-Saharan Africa, treponematosis originated from nonhuman primates as a childhood disease (yaws) transmitted by skin-skin contact. The bacteria evolved alongside humans in migrating hunter-gatherer populations throughout the Paleolithic. Eventually, groups moved into drier climates, and the ancestral treponeme common to apes and man retreated to moister areas of the body (manifested as endemic syphilis, or bejel). 
    Populations crossing the Bering Strait into the New World from Asia carried the endemic syphilis, and mutations accumulated until the bacteria evolved into contemporary pinta and bejel. Eventually, the climatic change in the New World caused a shift back to yaws, and the crowded, unsanitary conditions in the Americas during the Neolithic facilitated the spread through increased child-child contact.
    Meanwhile, in the Old World in 4000 B.C., urbanization improved community hygiene, and sexual contact was the only way to permit transmission of treponemas, as promiscuity and prostitution increased the spread of the disease.

Unfortunately, it is difficult to definitively pinpoint the origin of syphilis, because skeletal evidence must be proven to be both ancient and syphilitic. However, an exhaustive review of the documentary and skeletal evidence of treponematosis by Baker and Armelagos conclude that nonvenereal treponemal infection is a New World disease that spread to the Old World and became a venereal disease following European contact.

YAWS
T. pallidum pertenue

sabre tibia

BEJEL (Endemic syphilis)
T. pallidum endemicum

• Single does antibiotic with benzathine penicillin (or tetracycline, doxycycline, erythromycin)