Salmonella or a catastrophic epidemic in Mexico in the 16th century

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published online this week, researchers have successfully identified the genome of intestinal salmonella from the teeth of victims of the 16th-century Mexican epidemic. The study describes the first known emergence of salmonella in the Americas, which appears to have been brought by Europeans and had a devastating effect on the region.
is well known that it is difficult to identify infectious pathogens from human remains, as most pathogens do not leave traces on bones. Using a new identification technique called MALT, the researchers identified the DNA sequence of salmonella from the teeth of 10 indigenous Mexicans. The men were buried in the cemetery of "cocoliztli" (the Nawat word for "plague"), dating back to the early days of European contact with the region. In the past, it has been suggested, based on the history of symptoms of the cocoliztli epidemic, that the outbreak was caused by some form of typhoid fever. This identification of intestinal salmonella, the bacteria that causes typhoid fever, confirms this view.
because Mexico's indigenous people had never been exposed to intestinal salmonella (known to exist in medieval Europe) and were highly susceptible to infection, this may also explain the high mortality rate in cocoliztli. In the centuries since the first contact between Europeans and Americans, they have been infected with a variety of diseases in a similar manner, such as small flowers, influenza and measles. Like typhoid fever, none of these diseases leave traces on bones, but the new technique MALT is expected to help identify pathogenic DNA viruses and bacterial pathogens in the future. (Source: Feng Weiwei, China Science Daily)