Latest news with #Mycobacteriumlepromatosis
Time of India
4 days ago
- Health
- Time of India
Secret leprosy infected the Americas before European arrival
Representative image (AP) What to know: Leprosy is one of the oldest human diseases and originated in Eurasia or Africa A new study has found a different species of leprosy-causing bacteria existed in the Americas before European settlement. Scientists once believed Europeans brought leprosy to the American continents via infection from the bacterial species Mycobacterium leprae. But now a new study published in the journal Science reveals that a different form of leprosy-causing bacteria — called Mycobacterium lepromatosis — was already circulating in the Americas for at least one thousand years. Leprosy was therefore already affecting American indigenous peoples well before European colonization. Mycobacterium lepromatosis in America The study authors analyzed more than 800 samples taken from ancient remains in Canada and Argentina. The genomes of the bacteria taken from the samples were reconstructed, analyzed, and dated. Comparisons between the samples showed the bacterial genomes were of distinctive branches of the lepromatosis species at each end of the continent. However, they remained genetically similar. This suggested that the bacteria species had spread rapidly across the Americas, probably covering the landmass in just a few hundred years. Leprosy is caused by two bacteria species, not one. Leprosy is an ancient disease Leprosy has been infecting humans for thousands of years. The disease presents as multiple numbing skin lesions. If left untreated, it can result in nerve damage, muscle weakness, paralysis and blindness. Today, leprosy can be treated with antibiotics, but ancient sufferers weren't so fortunate. Skeletal records from 2,000BCE have been found in India with traces of the disease caused by Mycobacterium leprae. These are matched by written records of leprosy cases in ancient literature from Indian, Chinese and African civilizations, as well as stories in the Abrahamic religions. Often, these ancient descriptions associated the affliction with stigmas of immorality or ritual uncleanliness. But in 1874 the Norwegian doctor Gerhard Armauer Hansen discovered that leprosy was caused by the microscopic organism Mycobacterium leprae. In 2008, doctors in Mexico found another leprosy-causing bacteria species — Mycobacterium lepromatosis — in a leprosy patient. Before this, it was believed leprae was the only pathogen capable of causing the disease. Now both forms of the bacteria are known to cause it. Europeans spread diseases, leprosy too Nicolas Rascovan, head of the Microbial Paleogenomics Unit at the Pasteur Institut in France led the investigation. He and his colleagues estimate lepromatosis and leprae diverged from a common ancestor about one million years ago. "The diversification happened probably independent of humans," Rascovan told DW. The arrival of the first European fleets to the Americas in 1492 marked the introduction of new diseases to the Americas. Leprosy — in the form of the leprae bacterium — was among them. Archaeological evidence has shown leprae migrated with human groups out of Africa and into Asia and Europe around 40,000 years ago. Its introduction to the Americas, along with other diseases, by Europeans devastated indigenous communities and intensified the impact of pathogens that were already circulating before colonization. The discovery of lepromatosis' longer history on the continent further highlights the diversity of pathogens and their complex relationship with humans throughout history, said Rascovan. "Europeans had a very important impact by bringing this new species [leprae] that was absent in America," he said. Leprosy track and trace Rascovan hopes the presence of lepromatosis in the archeological record will improve understanding of pre-colonial disease, especially in the absence of written records. In addition, the study helps understand modern cases of leprosy, especially how it could make the jump from animals like squirrels to humans. "Our work is giving the kick start to really start analyzing, monitoring and understanding the diversity of natural reservoirs [disease carriers]," said Rascovan. He said monitoring the disease and preventing spillovers from animals to humans should be a priority. The disease is still prevalent today — 200,000 cases are reported each year globally. Brazil, India and Indonesia still report more than 10,000 new cases annually, according to WHO data.
DW
5 days ago
- Health
- DW
Secret leprosy infected the Americas before European arrival – DW – 06/04/2025
European colonizers were thought to have brought leprosy to the Americas, but a new study reveals it existed there for thousands of years and spread by a recently discovered bacteria species. What to know: Leprosy is one of the oldest human diseases and originated in Eurasia or Africa. A new study has found a different species of leprosy-causing bacteria existed in the Americas before European settlement. Scientists once believed Europeans brought leprosy to the American continents via infection from the bacterial species Mycobacterium leprae. But now a new study published in the journal Science reveals that a different form of leprosy-causing bacteria — called Mycobacterium lepromatosis — was already circulating in the Americas for at least one thousand years. Leprosy was therefore already affecting American indigenous peoples well before European colonization. For years, it was believed Mycobacterium leprae bacteria were the only cause of leprosy. That changed with the discovery of a new leprosy-causing Mycobacterium in 2008. Image: public domain Mycobacterium lepromatosis in America The study authors analyzed more than 800 samples taken from ancient remains in Canada and Argentina. The genomes of the bacteria taken from the samples were reconstructed, analyzed, and dated. Comparisons between the samples showed the bacterial genomes were of distinctive branches of the lepromatosis species at each end of the continent. However, they remained genetically similar. This suggested that the bacteria species had spread rapidly across the Americas, probably covering the landmass in just a few hundred years. Leprosy is caused by two bacteria species, not one. Leprosy is an ancient disease Leprosy has been infecting humans for thousands of years. Skeletal records from 2,000BCE have been found in India with traces of the disease caused by Mycobacterium leprae. These are matched by textual records of leprosy cases in ancient literature from Indian, Chinese and African civilizations, as well as stories in the Abrahamic religions. Often, these ancient descriptions associated the affliction with stigmas of immorality or ritual uncleanliness. But in 1874 the Norwegian doctor Gerhard Armauer Hansen discovered that leprosy was caused by the microscopic organism Mycobacterium leprae. In 2008, doctors in Mexico found another leprosy-causing bacteria species — Mycobacterium lepromatosis — in a leprosy patient. Before this, it was believed leprae was the only pathogen capable of causing the disease. Now both forms of the bacteria are known to cause it. Leprosy has been stigmatized around the world for thousands of years, but with quick medical treatment, its dangerous symptoms can be reduced Image: Nyein Chan Naing/dpa/picture alliance Europeans spread diseases, leprosy too Nicolas Rascovan, head of the Microbial Paleogenomics Unit at the Pasteur Institut in France led the investigation. He and his colleagues estimate lepromatosis and leprae diverged from a common ancestor about one million years ago. "The diversification happened probably independent of humans," Rascovan told DW. The arrival of the first European fleets to the Americas in 1492 marked the introduction of new diseases to the Americas. Leprosy — in the form of the leprae bacterium — was among them. Archaeological evidence has shown leprae migrated with human groups out of Africa and into Asia and Europe around 40,000 years ago. Its introduction to the Americas along with other diseases by Europeans devastated indigenous communities and intensified the impact of pathogens that were already circulating before colonization. The discovery of lepromatosis' longer history on the continent further highlights the diversity of pathogens and their complex relationship with humans throughout history, said Rascovan. "Europeans had a very important impact by bringing this new species [leprae] that was absent in America," he said. Indonesian leprosy survivors stepping over social stigmas To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Leprosy track and trace Rascovan hopes the presence of lepromatosis in the archeological record will improve understanding of pre-colonial disease, especially in the absence of written records. In addition, the study helps understand modern cases of leprosy, especially how it could make the jump from animals like squirrels to humans. "Our work is giving the kick start to really start analyzing, monitoring and understanding the diversity of natural reservoirs [disease carriers],' said Rascovan. He said monitoring the disease and preventing spillovers from animals to humans should be a priority. The disease is still prevalent today — 200,000 cases are reported each year globally. Brazil, India and Indonesia still report more than 10,000 new cases annually, according to WHO data. The disease presents as multiple numbing skin lesions. If left untreated, the disease can result in nerve damage, muscle weakness, paralysis and blindness. Today, leprosy can be treated with antibiotics, but ancient sufferers weren't so fortunate. Edited by: Fred Schwaller
Saba Yemen
6 days ago
- Health
- Saba Yemen
Study: Leprosy Was Latent in Americas Long Before Colonization
Washington - (Saba): A recent scientific study has found that leprosy was latent in the Americas long before European colonization, contrary to the long-held belief that the disease was introduced by European settlers. This suggests that Native Americans had already been dying from the disease for centuries. The primary cause of leprosy is known to be a bacterium called Mycobacterium leprae, and researchers still believe that Europeans introduced it to the Americas. However, a lesser-known cause appears to have been identified at that time. The new study, conducted by an international team of researchers and published in the journal Science, found that another bacterium, Mycobacterium lepromatosis—a less common cause of leprosy—was present in the DNA of ancient human remains from Canada and Argentina dating back at least 1,000 years. "This discovery changes our understanding of the history of leprosy in the Americas," says genomicist Maria Lopopolo of the Pasteur Institute in France. "It shows that a form of the disease was already endemic among indigenous populations long before the arrival of Europeans." Mycobacterium leprae was first detected in a patient in the United States in 2008 and has since also been found in red squirrels (Sciurus vulgaris) in the United Kingdom. Researchers suggest it likely spread from the United States to the United Kingdom in the 19th century. In collaboration with local indigenous communities, regarding the handling of ancestral remains, the researchers analyzed the DNA of a total of 389 ancient human samples and 408 modern human samples. Based on the results, they constructed a genetic family tree for the leprosy bacteria. Although the ancient Canadian and Argentine samples were separated by thousands of kilometers, they were remarkably genetically similar. This suggests a rapid spread of leprosy across The Americas. Based on the timeline compiled from DNA, the various strains of Mycobacterium leprae likely diverged from a common ancestor more than 9,000 years ago. With all these millennia of evolution, the team says there are likely more diverse forms of the bacteria still waiting to be discovered in the Americas. "We are only just beginning to uncover the diversity and global movement of this newly discovered pathogen," says biologist Nicolas Rascovin of the Pasteur Institute. This study allows us to hypothesize the existence of unknown animal reservoirs for this virus. All of this adds a valuable dimension to our understanding of the history of the Americas and of leprosy. It provides researchers with crucial data regarding the evolution and diversity of the disease. Infectious diseases have played a significant role in the history of North, South, and Central America, with the arrival of Europeans bringing with them a range of new pathogens for which indigenous communities were biologically unprepared. We now know that the leprosy aspect is more complex than previously thought. Around 200,000 new cases of the disease are reported globally each year, even though it is now treatable and curable with modern medicines. 'This study clearly demonstrates how ancient and modern DNA can rewrite the history of human pathogens and help us better understand the epidemiology of contemporary infectious diseases,' says Rascovan. Whatsapp Telegram Email Print
