It has long been thought that Europeans brought tuberculosis with them into the Americas when searching for land. However, new research suggests that tuberculosis had made its arrival long before Christopher Columbus set foot in the New World.
According to ASU News on Wednesday, researchers believe that it was actually sea lions that were responsible for transmitting tuberculosis to people in the Americas. A team of researchers studying tuberculosis found that when they studied three 1,000-year-old skeletons from Peru, the tuberculosis they found was more closely related to a strain carried by seals and sea lions. An Arizona state University professor of Human Evolution and Social Change was part of the study and she stated, “What we found was really surprising. The ancient strains are distinct from any known human-adapted tuberculosis strain.”
It is thought that the seals and sea lions were infected with tuberculosis carried by another species in Africa and brought it with them on their journey across the ocean. The coastal people of South America then likely ate an infected seal or sea lion and became infected themselves.
Currently, the strains of tuberculosis that are still circulating are only related to those that originated in Europe. It is thought that when the tuberculosis that came from seals finally was met with the tuberculosis from Europe, the European-originating strain won out and the older strain was completely replaced.
This is significant in that the strain of tuberculosis that we encounter today is actually much younger than previously thought. It was thought that the transmission of tuberculosis had followed along with human migratory patterns when people were traveling long distances and would come into contact with those who hadn’t previously been introduced to the disease. With this information, now the researchers want to look at the relationships current strains of tuberculosis have to older versions. They’d also like to single out more versions from ancient remains.
Jane Buikstra, a collaborator on the study stated, “Tuberculosis is a disease that is on the rise again, worldwide. This study and further research will help us understand how the disease is transmitted and how the disease may evolve.” In the face of the current Ebola epidemic the world is currently facing, such research would be gladly welcomed, considering tuberculosis is described as one of the most persistent and deadliest infectious diseases in the world.