Bacterial DNA reveals salmonella may have wiped out the Aztecs

A couple of new studies reveal that salmonella may have been the cause of mass devastation to the Aztec civilization, at least according to the DNA of bacterium pulled from burial locations in Mexico. The nation's native inhabitants were hit with a severe pestilence of some sort, one powerful enough to have wiped out as much as 80-percent of the population. The exact cause of that devastation has been a source of mystery.

The decimation of Mexico's native population followed the arrival of European colonization. In the early 1500s, just before Spanish conquistadors arrived, there were about 25 million individuals in the region. Only 100 years later, and due in part to the epidemic, only about a million individuals in the native population remained.

It was one of the worst recorded epidemics ever, and it happened in two batches, one in 1545 and another 1576. A big mystery has surrounded the pathogen behind the epidemic, though some diseases like smallpox have since been ruled out. Now we may finally have the answer thanks to bacterium harvested from the teeth of individuals buried in Southern Mexico, with the graves dating back to the relevant time period.

The DNA of this bacteria is linked to salmonella, particularly a strain called "Paratyphi C" that is commonly found in developing nations. When infected with this salmonella, victims develop a condition called enteric fever which, if not treated, will kill between 10 and 15-percent of afflicted individuals.

SOURCE: Nature