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View Full Version : Origin and control of modern syphillis



Angela
07-12-16, 16:34
It's actually the increasing lack of control as these strains evolve and develop resistance to antibiotics. The only thing that still works is perhaps penicillin. I don't understand why there aren't more public health warnings about this. It sounds pretty dire.

See: Natasha Arora et al
http://www.nature.com/articles/nmicrobiol2016245.epdf?shared_access_token=wcDkQk1 tZ7QJ0gBDy-iHb9RgN0jAjWel9jnR3ZoTv0MUGiEHcCbkW0uWqU-Z8_VoHzz_trh16LxRUxzjGucZJ6LTuUBs4GRj8thOLEGj05Cx3 aShFcWft-OZy6_PH_kiO7jj0ojQqAGbVwi4pDUAyHyc480OLBtDodBbQaQX xJAZU1q0sxrqFcar_YqR5H8z

"The abrupt onslaught of the syphilis pandemic that started inthe late fifteenth century established this devastating infec-
tious disease as one of the most feared in human history
1
.
Surprisingly, despite the availability of effective antibiotic
treatment since the mid-twentieth century, this bacterial infec-
tion, which is caused by Treponema pallidum subsp. pallidum
(TPA), has been re-emerging globally in the last few decades
with an estimated 10.6 million cases in 2008 (ref. 2).
Although resistance to penicillin has not yet been identified,
an increasing number of strains fail to respond to the second-
line antibiotic azithromycin
3
. Little is known about the genetic
patterns in current infections or the evolutionary origins of
the disease due to the low quantities of treponemal DNA in
clinical samples and difficulties in cultivating the pathogen
4
.
Here, we used DNA capture and whole-genome sequencing to
successfully interrogate genome-wide variation from syphilis
patient specimens, combined with laboratory samples of TPA
and two other subspecies. Phylogenetic comparisons based
on the sequenced genomes indicate that the TPA strains exam-
ined share a common ancestor after the fifteenth century,
within the early modern era. Moreover, most contemporary
strains are azithromycin-resistant and are members of a glob-
ally dominant cluster, named here as SS14-Ω. The cluster diver-
sified from a common ancestor in the mid-twentieth century
subsequent to the discovery of antibiotics. Its recent phyloge-
netic divergence and global presence point to the emergence
of a pandemic strain cluster.

It would be interesting if someday researchers were able to trace it back to its actual origins, and thus could determine if it was indeed brought to Europe from the New World.

See:
https://en.wikipedia.org/wiki/History_of_syphilis