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New Study Suggests Columbus Brought Syphilis To Europe From New World
Did Columbus and his men introduce the syphilis pathogen into Renaissance Europe after contracting it during their voyage to the New World? Or does
syphilis have a much longer history in the Old World? The most comprehensive comparative genetic analysis conducted on the family of bacteria (the
treponemes) that cause syphilis and related diseases such as yaws, published Tuesday, January 15 in PLoS Neglected Tropical Diseases, supports the
so-called "Columbian theory" of syphilis's origins.
Kristin Harper (Emory University, Atlanta, USA) approached this centuries-old debate by using phylogenetics - the study of the evolutionary
relatedness between organisms - to study 26 geographically disparate strains of treponemes. The venereal syphilis-causing strains originated most
recently, and their closest relatives were strains collected in South America that cause the treponemal disease yaws.
"That supports the hypothesis that syphilis - or some progenitor - came from the New World," Harper says.
While it is generally agreed that the first recorded epidemic of syphilis occurred in Europe in 1495, controversy has raged ever since over the origin
of the pathogen.
Most of the evidence in recent years has come from bones of past civilizations in both New World and Old World sites, since chronic syphilis causes
skeletal lesions. In many cases, however, skeletal analysis is inconclusive, due to problems with pinpointing the age of the bones and the lack of
supporting epidemiological evidence.
Further complicating the research is the fact that the family of Treponema bacteria causes different diseases that share some symptoms but have
different modes of transmission. Syphilis is sexually transmitted, but yaws and endemic syphilis are tropical diseases that are transmitted through
skin-to-skin or oral contact. One hypothesis is that a subspecies of Treponema from the warm, moist climate of the tropical New World mutated into the
venereal, syphilis-causing subspecies to survive in the cooler and relatively more hygienic European environment.
The phylogenetic analysis indicated that yaws is an ancient infection in humans while venereal syphilis arose relatively recently. The study results
are especially significant due to the large number of different strains analyzed, including two never-before-sequenced strains of yaws from isolated
inhabitants of Guyana's interior. At Harper's request, the Guyana samples were collected during a medical mission by Ve'ahavta, the Canadian Jewish
Humanitarian and Relief Committee.
"Syphilis was a major killer in Europe during the Renaissance," says co-author George Armelagos, a skeletal biologist whose research put him at
the forefront of the syphilis debate 30 years ago. "Understanding its evolution is important not just for biology, but for understanding social and
political history. It could be argued that syphilis is one of the important early examples of globalization and disease, and globalization remains an
important factor in emerging diseases."
Harper KN, Ocampo PS, Steiner BM, George RW, Silverman MS, et al. (2008)
On the Origin of the Treponematoses: A Phylogenetic Approach.
PLoS Negl Trop Dis 2(1): e148. doi:10.1371/journal.pntd.0000148
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About PLoS Neglected Tropical Diseases
PLoS Neglected Tropical Diseases is a peer-reviewed, open-access journal devoted to the pathology, epidemiology,
prevention, treatment, and control of the neglected tropical diseases, as well as public policy relevant to this group of diseases. All works
published in PLoS Neglected Tropical Diseases are open access, which means that everything is immediately and freely available subject only to the
condition that the original authorship and source are properly attributed. The Public Library of Science uses the Creative Commons Attribution
License, and copyright is retained by the authors.
PLoS Neglected Tropical Diseases
About the Public Library of Science
The Public Library of Science (PLoS) is a non-profit organization of scientists and physicians committed to making the world's scientific and medical
literature a freely available public resource.
Public Library of Science
Nou studiu sugereazã Columbus adus sifilisul în Europa de la New World - New Study Suggests Columbus Brought Syphilis To Europe From New World - articole medicale engleza - startsanatate