An Ancient Mummy’s Tooth Could Rewrite Script of Scarlet Fever in the New World
When European explorers arrived in the New World, they brought horses, cattle, guns, and many diseases. With no defense against them, indigenous populations were ravaged by smallpox, cholera, measles, and other exotic diseases endemic to Europeans. The same was thought to be true for scarlet fever, but according to a new study published in Natural communicationsthis no longer appears to be the case.
Researchers from the Eurac Research Institute in Italy made the discovery while studying the genome of Bolivian mummies, remarkably well preserved thanks to the cool, dry air of the Andean highlands. Hidden in the tooth of a man who lived between 1283 and 1383, they discovered the DNA of Streptococcus pyogenicthe bacteria responsible for scarlet fever, indicating that it circulated among indigenous populations long before the arrival of Christopher Columbus.
The DNA was so well preserved that the researchers were able to reconstruct the bacteria’s entire genome from fragments. “It’s like putting together a puzzle without knowing the picture on the box,” study author Mohamed Sarhan said in a statement. Their analysis revealed that the bacteria was strikingly similar to modern strains and capable of causing disease, despite lacking certain disease-causing genes.
Read more: “How the disease actually spread in the Americas”
The tooth belonged to a man who ate a diet high in corn, indicating he likely led an agricultural life. According to the researchers, increased population density and reduced mobility linked to agriculture are more conducive to the spread of pathogens. To this end, their analysis of the bacterial genome suggests that S. pyogenes The strains diverged around 5,000 years ago, at a time when human populations were beginning to settle into larger groups. In other words, a change in lifestyle appears to have caused an explosion of S. pyogenes diversity.
But if scarlet fever didn’t kill European explorers, where did it come from?
He may have made the journey with the first humans who crossed the frozen Bering Strait to the Americas about 22,000 years ago, but researchers can’t be sure.
Regardless, this research serves as another reminder that human history can be at least partially informed by the pathogens that co-evolved with us.
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Main image: Archivist / Adobe Stock
