No clue to be honest. Some think some did catch it but mistook it for a European disease. It might be that virus was less viral then the European ones, who knows. The cocoliztli theory is just a theory spread by some scientists in the field. Apparently some think it's still around today in remote areas. But even those who believe in this theory concede it was worsened by the fact that I dunno....there's so much chaos with the Europeans coming and their already weakened immune systems screwed things up more.....not to mention drought.
I actually meant to edit my post earlier, but if you're talking about
this, at least to me what looks like happened is cocoliztli and smallpox almost had a contest to see who could kill people fastest (as Ebola shows, an extremely lethal disease could show up and still not do well because it killed people too quickly to be spread), which meant that any Spaniard who caught it quickly succumbed to it before it made it's way to Europe, and since the population of the Mexican basin dropped so dramatically, the disease soon found it hard to spread. Plus, Mexico was not a settler colony like the Thirteen Colonies were. According to Wiki, maybe 650,000 people immigrated from Spain to Mexico, far less than the millions that poured into the US. Thus there just weren't as many opportunities for it to catch a ride to Europe. Cocoliztli had the "benefit" of being a kind of salmonella that was essentially unknown to Europe, and cause hemorrhaging. Salmonella is spread when something contaminated with Salmonella is accidentally ingested or ends up another way getting into the body. The hemorrhaging makes it that much easier to spread because since someone is literally bleeding out everywhere, the likelihood of some blood that is contaminated landing on something that would later be eaten is a lot higher. As a counterpoint,
this article describes how the Spaniards seemed almost unaffected while natives around them died in droves. On one hand, the traditional explanation for this is that the Spaniards had stronger immune systems from dealing with things such as the black death. On the other hand, the lack of transmission could be explained by the intense social stratification of Spanish Mexican society. Native Americans IIRC were almost untouchables healthy, much less between a Spanish conquistador and their slave who was bleeding from their orifices, thus resulting in no real spread. The Spanish population was also small, with Mexico city proper only hosting around a four thousand Spaniards, and most of them soldiers, allowing for this stratification to continue. Essentially, the Spanish unwittingly quarantined themselves.
There's another disease called matlazahuatl which was similar. It only gets a footnote on the wikipedia page but upon further research I feel like it deserves it's own little section in this rant. Matlazahuatl was a disease that affected Mesoamerica in the wet season, while Cocoliztli affected it in the dry season. It was a significant part of ancient Mexican basin civilization, to the point that a massive outbreak of matlazahuatl is what took out the Toltecs, which the Aztecs saw as their direct predecessor (in the same way the Romans saw the Greek empires as their precursor). It had similar but milder symptoms, but had two things that separated it from Cocoliztli. One is that it was somewhat milder. The second is that it
primarily affected people 20-40. (Also, a lot of sources in all of these are in Spanish, so it is a bit hard to dig up). Interestingly, this is around the same age as a lot of farmers and workers would be in Europe. Way, way,
way less is known about matlazahuatl than is known about cocoliztli (which even then is minimal), but the University of Barcelona proposes it is some form of Hepatitis. An article from the 1800's
claims that it is noncontagious and does not (generally) infect Europeans. However, I could find no information about matlazahuatl outbreaks between 1737 (
which did infect Spaniards, albeit at reduced rates compared to Native Americans, though this could be explained by the compromised immune systems in Native Americans due to the stresses of colonization) and 1821, which leads me to think that the described disease is somewhat different (along with factors that the described disease seemed to affect people 30-50, while earlier sources describe it infecting those about a decade younger).
If these two diseases were to have spread to Europe, the results would have been devastating. Matlazahuatl would have probably arrived first since iirc the years the Spanish were more involved were wet-season years due to the crop growth and Mesoamerica around the time of the Spanish conquest was in a wet season, though correct me if I'm wrong. Perhaps a Spanish missionary-hospitaler, in the mountains of Mexico, ends up getting some blood on his robe he forgets to wash off, and contracts it on the way back to Spain. Soon, his whole convent is dead, with many in the surrounding city having high fevers and intermittent bleeding. As the disease spreads through Spain, panic sets in as the disease burns its way through Europe, with perhaps a 20% fatality rate. The worst is yet to come, however. Cocoliztli arrives in an absolutely devastating way not seen since the Black Death. In Iberia, 60% of the population dies from Cocoliztli, after a fifth had died from Matlazahuatl. (Note that in Mesoamerica, the rate was perhaps 75-90% so I am deflating them a little to account for European disease resistance). The population of Spain drops from 7,400,000 to 2,368,000. Death rates elsewhere are somewhat less but still comparable. Europe grinds to a standstill...
Holy shit this took me forever to write. However, there just
isn't any information on the two diseases out there, but this has inspired me to maybe even write a book on it. We'll see what happens.
