Washington: In 1492, Christopher Columbus sailed the Atlantic Ocean to discover America, but when he returned from his historic voyages he brought with him a new disease to Europe, claims a new study.
   
The study based on new skeletal evidence suggests that Columbus and his crew not only introduced the Old World to the New World, but brought back syphilis as well.
   
Syphilis is caused by Treponema pallidum bacteria, and is usually curable nowadays with antibiotics. Untreated, it can damage the heart, brain, eyes and bones; it can also be fatal.
   
The first known epidemic of syphilis occurred during the Renaissance in 1495. Initially its plague broke out among the army of Charles the VIII after the French King invaded Naples.
   
It then proceeded to devastate Europe, said researcher George Armelagos, a skeletal biologist at Emory University in Atlanta, who was the first to doubt the so-called Columbian theory for syphilis decades ago.
   
"I laughed at the idea that a small group of sailors brought back this disease that caused this major European epidemic," he said.
     
Critics have proposed that syphilis had always bedeviled the Old World but simply had not been set apart from other rotting diseases such as leprosy until 1500 or so.
   
However, upon further investigation, Armelagos and his colleagues got a shock -- all of the available evidence they found supported the Columbian theory.
   
"It was a paradigm shift," Armelagos said. Then, genetic analysis by Armelagos and his collaborators of syphilis's family of bacteria lent further support to the theory.
   
Armelagos and his colleagues took a closer look at all the data from the 16 prior reports.
   
They found that most of the skeletal material didn't actually meet at least one of the standard diagnostic criteria for chronic syphilis, such as pitting on the skull, known as caries sicca, and pitting and swelling of the long bones.
   
"There's no really good evidence of a syphilis case before 1492 in Europe," Armelagos said.
   
The findings are detailed in the current Yearbook of Physical Anthropology.

The 16 reports that did meet the criteria for syphilis came from coastal regions where seafood was a large part of the diet. This seafood contains "old carbon" from deep ocean waters. As such, they might fall prey to the so-called "marine reservoir effect" that can throw off radiocarbon dating of a skeleton by hundreds or even thousands of years.
   
To adjust for this effect, the researchers figured out the amount of seafood these people ate when alive. Since our bodies constantly break down and rebuild bones, measurements of bone-collagen protein can provide a record of diet.
   
"Once we adjusted for the marine signature, all of the skeletons that showed definite signs of treponemal disease appeared to be dated to after Columbus returned to Europe," said Kristin Harper, an evolutionary biologist at Emory.
   
"What it really shows to me is that globalisation of disease is not a modern condition. In 1492, you had the transmission of a number of diseases from Europe that decimated Native Americans, and you also had disease from Native Americans to Europe," Armelagos said.
   
"The lesson we can learn for today from history is that these epidemics are the result of unrest."

(Agencies)