Results from a new study in Nature Ecology and Evolution indicated that Salmonella may have played a significant role in an epidemic that killed over 7 million Aztecs during the 16th century.
The connection to Salmonella was discovered when the research team compared DNA extracted from the teeth of 10 victims of the epidemic. The researchers used a recent technological advance, a computer program called MALT, which analyzes DNA fragments and identifies the types of bacteria that are present. Before the introduction of the algorithm, researchers were unable to compare the DNA across the board or identify potential connections due to the nature of infectious diseases to leave very small traces of evidence.
Although the study found the presence of Salmonella enterica paratyphi C bacteria, there is no indication of how the epidemic originated. The authors, including Kirsten Bos, PhD, a molecular paleopathologist at the Max Planck Institute in Germany, indicate that there is no evidence to support the idea that the epidemic was brought about by Europeans who invaded the area around the time prior to the outbreak.
The epidemic that heavily contributed to the destruction of the Aztec Empire may not have been brought about by Europeans, but the new settlers still have potential to be at fault for bringing new illnesses to the Aztecs. Dr. Bos explained to NPR that the combination of new European livestock and social disruption increased the indigenous group’s vulnerability to infectious diseases. The origins of infectious disease are critical to researchers and present the opportunity for the topic to be explored in the future.