One of History's Worst Epidemics and its Potential Cause
Overview
The article investigates a historical epidemic in the 16th century, particularly affecting native Mesoamericans, potentially caused by Salmonella enterica.
The epidemic is referred to as "cocoliztli" in Nahuatl, marked by severe symptoms and high mortality.
New DNA evidence suggests a connection to salmonella, challenging previous notions of hemorrhagic fever.
Key Details
Background
Cocoliztli Epidemic: First appeared in Mexico (then New Spain) in the 16th century.
Characterized by symptoms unlike any seen before: jaundice, bleeding from orifices, hallucinations, and convulsions.
Estimated 45% of the native population perished.
Historical records previously suggested a hemorrhagic fever similar to Ebola.
New Research Findings
DNA Evidence: Researchers analyzed DNA from 29 skeletons unearthed from Teposcolula Yucundaa in Oaxaca, Mexico.
24 skeletons from the 1545 outbreak period.
5 skeletons from a cemetery predating European contact.
Salmonella Detection: DNA extracted from the teeth linked to Salmonella enterica, particularly paratyphi C, suggests enteric fever.
Found in 10 skeletons corresponding to the outbreak.
Absent in pre-contact skeletons.
Implications
European Connection: Suggests Europeans might have introduced salmonella through livestock or human carriers.
Similar salmonella found in an 800-year-old Norwegian skeleton.
Local Impact: Indigenous populations possibly had little immunity due to a lack of previous exposure.
Contributed to the epidemic alongside environmental factors like drought and malnutrition.
Scientific Opinions
Some experts caution against attributing the epidemic solely to salmonella.
Possible it was one of several pathogens involved.
Symptoms described historically do not completely align with salmonella infections.
The possibility of massive bacterial infection could mimic hemorrhagic fever symptoms.
Conclusion
While the connection to salmonella offers a new perspective, it is uncertain if it was the exclusive cause of the cocoliztli.
Further research needed to fully understand the epidemic's dynamics and contributing factors.
References
Correction note: Global cases of enteric fever exceed 21 million annually, with fewer than 6000 in the U.S.