New research indicates that leprosy existed in the Americas long before European explorers arrived, challenging previous historical assumptions about the disease’s origins.
Recent findings from scientists at the Institut Pasteur in Paris, in collaboration with a U.S. university, have revealed that a second species of bacteria responsible for leprosy, known as Mycobacterium lepromatosis, was present in the Americas well before the arrival of European explorers. This discovery significantly alters the historical narrative surrounding the disease, which was previously thought to have been introduced by European settlers.
Historically, it was believed that the bacterium Mycobacterium leprae was the sole cause of leprosy, or Hansen’s disease, in the Americas, and that it was spread by early European explorers and settlers. However, the identification of Mycobacterium lepromatosis suggests that an existing strain of the bacteria was already endemic to the continent, challenging the long-held belief that Europeans were responsible for its introduction.
According to researchers, Mycobacterium lepromatosis existed and infected humans for at least 1,000 years prior to European contact. Dr. Maria Lopopolo, the first author of the study and a researcher at the Laboratory of Microbial Paleogenomics at the Institut Pasteur, emphasized the significance of this finding. “This discovery transforms our understanding of the history of leprosy in America. It shows that a form of the disease was already endemic among Indigenous populations well before the Europeans arrived,” she stated.
The study, which involved collaboration with the French National Center for Scientific Research and the University of Colorado, was initiated after Mycobacterium lepromatosis was first identified in a Mexican patient in 2008 and later in red squirrels in the British Isles in 2016. Utilizing advanced genetic techniques, researchers reconstructed the genomes of Mycobacterium lepromatosis from ancient individuals in Argentina and Canada. The genetic analysis revealed that the two strains from these regions were closely related, indicating that the bacteria spread rapidly across the continent.
The results confirmed that Mycobacterium lepromatosis had already disseminated throughout North and South America prior to European exploration. The research team worked closely with Indigenous communities, various international institutions, and archaeologists, analyzing over 800 DNA samples from ancient human remains and recent medical cases exhibiting signs of leprosy.
Nicolás Rascovan, the lead author of the study at the Institut Pasteur, remarked on the implications of their findings, stating, “We are just beginning to uncover the diversity and global movements of this recently identified pathogen. This study allows us to hypothesize that there might be unknown animal reservoirs.” This suggests that the understanding of leprosy’s transmission and its historical context may be more complex than previously thought.
The Centers for Disease Control and Prevention (CDC) notes that leprosy can affect the nerves, skin, and eyes of those infected, but it is treatable with antibiotics. Currently, there are approximately 225 reported cases in the U.S. and around 250,000 cases worldwide, according to the CDC.
This groundbreaking research not only sheds light on the historical presence of leprosy in the Americas but also opens up new avenues for understanding the disease’s transmission and its impact on Indigenous populations. As scientists continue to explore the genetic diversity of Mycobacterium lepromatosis, the implications for public health and historical narratives surrounding infectious diseases may evolve further.
These findings underscore the importance of ongoing research in microbial paleogenomics and the need to reconsider historical assumptions about disease spread and its effects on populations. The study serves as a reminder of the complex interplay between human history and infectious diseases, highlighting the necessity for continued investigation into the origins and evolution of pathogens.
According to Fox News, the implications of this research are profound, prompting a reevaluation of the historical context of leprosy in the Americas.