When most people think of leprosy, they picture history books or ancient tales. The disease is rarely linked to early populations in the Americas. However, new research challenges that assumption in a surprising way. A recent study published in Nature Communications sheds new light.
Researchers studied two ancient skeletons from northern Chile. They found DNA from Mycobacterium lepromatosis, a rare leprosy-causing bacterium. This species causes Hansen’s disease, a lesser-known form of leprosy. The bones are about 4,000 years old.
This pushes back the known history of leprosy in the region. Until now, experts believed leprosy arrived with European colonizers. There was no confirmed bone evidence before the colonial era. These findings raise new questions about leprosy’s spread and origins.
Most known cases involve Mycobacterium leprae, which came from Eurasia. M. lepromatosis, by contrast, may have evolved in the Americas. The two bacteria likely emerged on opposite sides of the world. This discovery reshapes how scientists understand the disease’s global history.