So I read an article a while ago which interested me immensely, and this article was about how a bacteria in the sixteenth century might've wiped out 80 percent of Mexico's population, for comparison, the Black Death wiped one-third of Europe's population while this wiped four-fifths of Mexico.
How did this start? Well firstly, we all know or at least acknowledged that personal health and sanitation weren't everybody's top priorities, there was an ongoing war, therefore, epidemics were on the rise, thus the life expectancy back then was lower than what it is now.
The mysterious cause of this wasn't known until recently when scientists were accessing the bones of the victims and successfully extracted genetic evidence that led to bacterium Salmonella enterica, which is a rod-shaped gram-negative bacteria, symptoms include abdominal cramps, fever, bleeding, and dysentery.
Salmonella infections could be caused when raw meat or food is not properly cooked, which could be one of the reasons why it happened in New Mexico back in the 1500s.
Just like the Black Death, there is also a possibility that the disease was brought into the country by outsiders, and speculations have concluded that this was brought by invaders who had unleashed pathogens into the old world, including typhoid and smallpox.
DNA was also extracted from the teeth of the victims that were excavated in the highland region of Mexico, and the sample of three tooths had narrowed the finding to another bacteria known as S. Parathyi C, which is one of the three serotypes of Salmonella enterica, DNA was also extracted from the non-epidemic victims to rule out the normal microbes that could've been in the system at the time. Further research had also shown that this was an old world plague and had been detected in Europe back in the 1200s.
Yet, there has skepticism on the research, with some stating that the research is avoiding the possibilities of how other bacteria could've been the cause of cocoliztli and also whether travelers or invaders had brought the pathogens into New Mexico.
So was the disease extremely infectious and deadly? Well, from my amateurish point of view, no, the reason this even got as many deaths as it did was that there was no or close healthcare system back then, there were still primary advancements or discoveries being made in the science realm.
Secondly, the epidemic of the bacteria was at its peak during war-time, and war-time never looked good in the old world, a different number of diseases and bacteria were plaguing every war-zone all around the world. At this time, famine would've increased as homes were being destroyed, food and water weren't clean or safe to drink but people had them anyway.
Additionally, the infection was also contagious and could've spread via direct contact of bodily fluids, which was definitely unknown to the victims at the time and made the infection easy to spread around the entire country since people were immigrating to other places since it was war-zone.
In conclusion, there is also a possibility that a number of other pathogens and bacterias could've played a role in the death of the many other people, but since this occurred more five hundred years ago, it is going to be hard to tell.
But if today's scientists spent the amount of time and dedication helping us make our future better than they did decoding the mysteries of the past that has no correlation to us, then we would be at a much better place than we are.