Spirochete Plagues in Pre-Contact Americas

Annoyingly, we still don't know whether Syphilis originated in the Americas, and was returned to the Old World by Columbus' first voyage. We may never actually know.

....But we do know some things. Things that may be relevant to Alternate Histories of the Americas.

There's seems to be room to speculate about pre-Colombian, intra-American epidemic diseases, and this without first hand-waving new domesticated species into being.
 

Brunaburh

Gone Fishin'
The problem is that sexual contact is not a great way to spread a disease in the absence of big cities.
 
The Pinta
To breeze through the basics, the debate on the origins of syphilis remains inconclusive. Its ancestral form - also the progenitor of friendly spirochete bacteria like yaws, pinta, and bejel ("endemic" or "non-venereal" syphilis) - had an ancient Old World origin. Syphilis' first indisputable appearance was at Naples in 1495; how it got there is unclear, but that it erupted across Europe as infected soldiers sloughed off the retreating French army is certain. The intervening period, between prehistory and 1495, is less clear.

The disease could have [1] remained in the Old World until the Age of Exploration, have [2] originated in the New World and eventually been picked up by Columbus' men, [3] speciated from a less awful disease on contact with Columbus' men, or [4] been present on both sides of the Atlantic - only coming to European attention when a particularly virulent form struck an army in a manner visible to historians.

The available evidence leans toward more toward the 2nd and 3rd possibilities than toward the 1st and 4th. That said, here's the breakdown:

Scenario 1-
Syphilis was present only in Europe for centuries prior to the Columbian Exchange (so the argument goes), but weaknesses in diagnosis saw it mistaken for leprosy. Supporting this thought is a matter of timing - in 1490, the pope ordered "leprosaria" abolished across Europe, theoretically setting huge numbers of lepers out on Europe's roads (from Mann's 1491). Syphilitic symptoms may have been described as early as by Hippocrates in classical Greece; skeletons in pre-contact Italy have been reported to have signs similar to the disease visible on their bones (the same applies to skeletons in Britain, according to 1491, and in Austria).

The leprosy idea isn't a hopeless argument, but the evidence is fairly weak. The disease has been known as "the great imitator" for the overlap of its symptoms with other contagions, suggesting that millennia-old descriptions are less than definitive. And the skeletal evidence is as yet non-peer-reviewed. But the scenario also falls down in denying an American presence of the disease.

Scenarios 2 and 3-
Evidence of an American origin seems strong. The appearance in Europe was remarkably sudden, virulent, and deadly - if the disease had been hiding under the cover of leprosy for centuries, it had clearly mutated to a new and more dangerous form at an awfully coincidental moment. That might instead suggest a foreign disease entering a virgin field.

Speaking from historical evidence, Ruy Díaz de Isla - a prominent Spanish doctor - claimed to have observed and attempted treatment on the crew of Columbus' first voyage. One of his patients, the captain of the Pinta, supposedly died of it within months of returning from the voyage. Contemporary Europeans (as opposed to the man-on-the-street accusations [It's the Neapolitan Sickness! The French Pox! Spanish Sickness! Canton Rash!]) were comfortable accepting its origin being West Indian. For some reason, this eye-witness perspective doesn't come up much in these debates, but that's a tangent.

And back to skeletons. Skeletons showing pathology similar to spirochete diseases such as yaws and syphilis were found across much of North and South America according to this study. Interestingly, southern populations (New Mexico, Hispaniola, Florida, and Ecuador) appeared to have syphilis, while northern ones (Ohio, Illinois, and Virginia) showed signs more reminiscent of yaws.

In terms of in vivo biology, there's still more evidence. Genetic studies suggest that yaws is the ancestral strain of the Trepanema family, and it is generally assumed to have originated in Africa, possibly spreading with the first human migrations from the continent. Endemic syphilis or bejel may have diverged from yaws early in human history, and currently hangs out in West Africa and the Eastern Med. This study tells a much more detailed story of the related diseases - suggesting an intermediate ancestral form of the disease separates the two confirmed Old World varieties from the two-or-three New World varieties. Those putative New World types? Syphilis, a variety of yaws found in Guyana (possibly representing a more baseline evolutionary branch for the Americas) and maybe? other parts of northern South America, and pinta.

Pinta itself is suggestive just by its existence. A close, but almost entirely harmless, relative of syphilis entirely localized to the New World. Pinta was historically present in tropical parts of Mexico, Central America, and Colombia.... yet nowhere in the Old World.

The more....wet....approach to biology thus demonstrates two syphilis relatives (pinta and the Guyanese yaws) currently limited to the tropical Americas, with the latter more closely related to syphilis than to confirmed Old World Trepanema spirochete critters. In parallel, dry biology suggests something like Treponema reached the Americas early, something like syphilis inhabited Meso-America, northern South America, the Caribbean, and adjacent areas from their early history, while something like yaws was present in North America as early as 500 years before contact.

Scenario 4-
It's also possible that related versions of the disease were on both sides of the Atlantic to begin with, but happened to really take off in 1495 Italy, for unknowable reasons. If that is the case, though.... It's still possible that a more virulent New World variety took center stage, catching attention the long-conflated-with-leprosy form had never earned. That would remove all questions raised about questionable skeletal remains, but how to square that with the genetic evidence? I don't know. It might not be possible.

This is, so far as I can tell, the possibility space we have to work with.

Which is to say we probably ought to consider writing these diseases into all of our New World timelines going forward.

(Thanks to @Jared , by the way, for pointing me in this direction.)

I'll return to this in another post with my speculation on what this could mean in our terms - for timeline writing.
 
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The problem is that sexual contact is not a great way to spread a disease in the absence of big cities.

Bruh, the continents were overflowing with cities, some of the largest cities in the world.

I mean you're not wrong in a general sense - there were very strong issues limiting the potential spread of any local disease. The few, geographically limited, and subpar beasts of burden effectively protected cities by limiting the scale and rate of trade. The failure to exploit the wheel had a similar effect. At the same time, zones of lower population-density with of myriad minor polities separated the larger civilizations from each other. Fewer large states also meant fewer long road networks. For that matter maritime trade was also fairly limited.

City size didn't top the list, though.
 

Brunaburh

Gone Fishin'
Bruh, the continents were overflowing with cities, some of the largest cities in the world.

I mean you're not wrong in a general sense - there were very strong issues limiting the potential spread of any local disease. The few, geographically limited, and subpar beasts of burden effectively protected cities by limiting the scale and rate of trade. The failure to exploit the wheel had a similar effect. At the same time, zones of lower population-density with of myriad minor polities separated the larger civilizations from each other. Fewer large states also meant fewer long road networks. For that matter maritime trade was also fairly limited.

City size didn't top the list, though.

The wheel's not as big a problem as the lack of animals strong enough to make use of it. While all your other points are correct, and are factors, I'm not convinced by the idea there were many big cities in the America. Apart from Cusco and Tenochtitlan
 
The wheel's not as big a problem as the lack of animals strong enough to make use of it. While all your other points are correct, and are factors, I'm not convinced by the idea there were many big cities in the America. Apart from Cusco and Tenochtitlan

I have to run to work, but check out estimates of the Mayans, to begin with. Coba and Calakmul weighed in at 50,000 people (so did early Monte Alban, and peak Cahokia, IIRC). Caracol 140,000 and El Pilar 180,000. Tikal 100,000.
 
So, what about the possibility of insect-borne diseases native to the New World, equivalent to yellow fever and malaria in Africa? Since New World primates are susceptible to human diseases and even have become reservoirs of insect-borne disease such as yellow fever, there is a possibility that a disease spread between monkeys by insects (which is more likely to survive than a directly spread one due to the fact that monkeys tend to be thinly spread out in small family groups) could jump the other way to humans.

A potentially good vector are the Lutzomyia sandflies, widespread across the Americas with species that feed on humans (and have been known to spread disease) surviving as far north as Virginia and as far south as Uruguay. For the epidemiology, looking at historical records of vesicular stomatitis and sandfly fever could show what an outbreak of a disease they spread could look like. For example, sandfly fever tends to hit invading armies pretty hard, as the Allies discovered when they pushed into Italy...
 

Brunaburh

Gone Fishin'
I have to run to work, but check out estimates of the Mayans, to begin with. Coba and Calakmul weighed in at 50,000 people (so did early Monte Alban, and peak Cahokia, IIRC). Caracol 140,000 and El Pilar 180,000. Tikal 100,000.

But the peaks weren't at the same time as the peaks of the cities further north and in Peru. Yes there was urbanism, but there was little contact between big cities, both because transport was difficult and cities were fewer and more spread out. The Mediterranean was the perfect locus for Syphilis, lots of urban areas surrounding a calm sea traversed by boats full of men who had sex with each other.
 
So, what about the possibility of insect-borne diseases native to the New World, equivalent to yellow fever and malaria in Africa? Since New World primates are susceptible to human diseases and even have become reservoirs of insect-borne disease such as yellow fever, there is a possibility that a disease spread between monkeys by insects (which is more likely to survive than a directly spread one due to the fact that monkeys tend to be thinly spread out in small family groups) could jump the other way to humans.

I don't know. Honestly, I wouldn't know where to start speculating, except in general terms.

And that's the problem. Speculating in general terms is, I believe, a deeply overused trope in these discussions. To read many TLs on the board, one might get the impression that the presence of multiple epidemic diseases was almost inevitable, and that the OTL New World was some sort of bizarre aberration. Inserting plausible diseases has real AH value, but that's not quite my intent here.

For one brief thread, I'd like to focus on the New World as it was, and speculate AH from there. Rather than wave our hands at some good guesses and conjure pestilence into being because it could have happened and might be more likely under X or Y scenarios.

A potentially good vector are the Lutzomyia sandflies, widespread across the Americas with species that feed on humans (and have been known to spread disease) surviving as far north as Virginia and as far south as Uruguay. For the epidemiology, looking at historical records of vesicular stomatitis and sandfly fever could show what an outbreak of a disease they spread could look like. For example, sandfly fever tends to hit invading armies pretty hard, as the Allies discovered when they pushed into Italy...

Interesting stuff. Do you know more about those two pathogens? Is there evidence those diseases or their relatives were present in the Americas? If not, then perhaps we should hold off for another time and place.

Lyme disease is caused by a spirochete.

Interesting! I'd had no idea. Looks like a fairly distant relative, though with these things it can be a bit hard to judge. Seems safe to say it diverged from yaws et al before humans evolved, though.

But the peaks weren't at the same time as the peaks of the cities further north and in Peru. Yes there was urbanism, but there was little contact between big cities, both because transport was difficult and cities were fewer and more spread out. The Mediterranean was the perfect locus for Syphilis, lots of urban areas surrounding a calm sea traversed by boats full of men who had sex with each other.

Indeed. It's clear that if syphilis was present, as seems very likely, most of the Americas was not conducive to its rapid proliferation. Reading between the lines, it seems like you may not be considering one big New World exception, but if you'll forgive me I'll save that for a later post.

I will take a jab at that sailor vector you emphasize. While that's probably how syphilis got to Europe in the first place, and it thrived in ports up to the modern era, contemporary accounts blame mercenaries on the march as the most responsible parties. Armed men marching all over a continent, expecting sex and often being able to pay for it - that seems to have been the decisive vector.

And of course that too was absent from (most of) the Americas.
 
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For one brief thread, I'd like to focus on the New World as it was, and speculate AH from there. Rather than wave our hands at some good guesses and conjure pestilence into being because it could have happened and might be more likely under X or Y scenarios.

All right then.

Some things to consider with spirochetes: they are slow acting, slow killing. The dramatic outbreak of syphillis in Europe in the 16th century may have been an unusually virulent strain. Syphillis in the modern era (as well as yaws) can be aysmptomatic for a long time, and when it does appear it can take a while to do damage. So you don't NEED big cities with a lot of trade to maintain the disease; it survives by not being too 'greedy' in killing and infecting hosts, giving the host time to spread it. It's this model of disease, rather than a 'black death' type of disease, that was most likely prevalent. To my knowledge there is no evidence of pre-contact mass graves indicating widespread, lethal epidemics destroying communities. On the other hand, mass graves indicating war captives or others killed or sacrificed are pretty well recorded by archaeologists.

Looking at diseases in the New World IOTL, we can speculate based on contact Native cultures and portrayals of disease in pre-contact art and writing. The Olmecs, for example, portrayed a wide variety of deformities in their artwork. Conquistadors lost among the Pueblo 'healed' an Indian experiencing stomach pains by blowing on his stomach, thus inadvertently starting a cult around themselves and demonstrating Native attitudes towards disease. Some of the earliest outbreaks of 'malaria' among Columbus' crew may have been local diseases they contracted that had similar symptoms-after all, why would the sailors not already contracted the disease through the mosquitoes stowing away on their boat?
 
The Waiting Plague
Syphilis was ready.

We don't know everything, not with absolute certainty, but that much at least is clear. Whatever its origin, the explosive outbreak from 1495 shows that by ~1490 syphilis either had an unusually virulent strain, or was highly adaptable - able to produce such a strain if set loose in a virgin field. Either way, the potential was undeniably there.

It's time to throw pretenses of scientific objectivity under the bus. New World origin may never be 100% certain, but in the business of alternate history we routinely make assumptions as large or larger based on less evidence. The option of writing a New World without syphilis can be reserved to author discretion for narrative purposes and the like, but for most AH writing, Syphilitic Americas really should be the default assumption.

If we assume that syphilis was both present in the Americas and highly virulent (or able to spontaneously become so), that suggests the New World was primed to suffer a self-inflicted epidemic. A rapidly-spreading infectious disease with clear symptoms and clear mode of transmission was ready to burst onto the scene and make epidemiology a visible part of New World history. But then it didn't.

The biology was there; something else was the obstacle. Obstacles, more likely. So, finally, to the point of this little thread: given enough time and the right PODS, obstacles can be removed.

When, where, and how might syphilis or post-syphilis epidemics have struck American peoples?
 
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