Smallpox epidemics and immunity

Hey all,

I posted a while back, and haven't posted since because I am finishing up college and so I'm too busy/disorganized to post regularly. But, I thought I'd pop in to ask a question that's been kind of bugging me (not because I have to think about it, but because I can't help but to think of these things).

How fast did smallpox move through the Americas after its introduction by Europeans? How easily could it spread through mainland pre-Columbian America? Most importantly, how long would it take for the native populations to recover from this epidemic and begin to develop immunity?

Basically, I'm curious to know if its possible to have smallpox introduced early to the Americas, and have some populations exposed to it long before they are contacted by Europeans (though presumably they would contract the disease from a population that was contacted by Europeans and Asians). It's doubtful that the disease would, say, cross from Newfoundland to Peru in time for the Inca to be ready for the Conquistadors, but I am curious as to how far it would go. Any thoughts?
 
How fast did smallpox move through the Americas after its introduction by Europeans?

Quite slow actually. The reason is, that smallpox makes you so sick, that you don't travel much. The Pacific coast was only reached in 1862, and the resulting epidemic was supported as a mean to get rid of the indians. There is a book detailing the spread of this epidemic:
http://www.historylink.org/index.cfmDisplayPage=output.cfm&file_id=5171

How easily could it spread through mainland pre-Columbian America?

If it is introduced to the eastern coast it will spread along the coast and into the great lakes region and the Mississipi within a century. The thinly populated great plains and rocky mountains would probably stop it from reaching the western coast. As the Aztecs migrated from the Southwestern parts of the USA into central Mexico smallpox would likly spread to Central america over the next two centuries. If given enough time the will from there also reach south America.

Most importantly, how long would it take for the native populations to recover from this epidemic and begin to develop immunity?

The population will recover within three to for generations. The reason the Indians didn't recover IOTL was that a) there were many diseases introduced b) the withe settlers took their land away.

And you don't develope immunity, all those who don't have it are simply killed by the disease leaving only immune persons. So the survivors of the first wave will already have a greatly enhanced resistance.

Basically, I'm curious to know if its possible to have smallpox introduced early to the Americas, and have some populations exposed to it long before they are contacted by Europeans (though presumably they would contract the disease from a population that was contacted by Europeans and Asians).

It is certainly possible, if not very likely. You could for instance have a carthagian ship sailing along the western coast of Afrcia carrying a infected sailor. As the smallpox spreads it kills or incapacitates enough sailors that the remainder looses control over the ship. Currents and trading winds carry the ship over the atlantic to the Americas, while the virus lingers in clothes and foodstuff. When the ship crashes on the American coast some curious indians get infected.

Another possibility would be the norse bringing smallpox to vinland. The main problem here is that the voyage from europe to vindland goes via Iceland and Greenland. This two stops form a quarantine slowing the spread of the disease.

It's doubtful that the disease would, say, cross from Newfoundland to Peru in time for the Inca to be ready for the Conquistadors, but I am curious as to how far it would go. Any thoughts?

While smallpox will have some problems to cross thinnly populated areas, as it does not need a vector to propagate it will invetiably spread to all human inhabited areas given enough time.

However that alone will not ready the indians for the Europeans. As many other diseases with a similar death toll like typhoid fever, influenza, tuberculosis and cholera were also introduced by the Europeans. So while beeing resistant to smallpox will certainly help, it won't be enough protect the indians against the diseases.
 
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Good point, there were many other diseases at the time. What would probably need to happen is gradual European or Asian contact, allowing disease and tech to spread inland. Sucks for the people on the coast, but the more inland peoples could recover and develop.

Kent-a cool idea, though since it's been done before I'd probably have it caused by the butterfly of some other major change.
 
One of the reasons the Caribbean natives(Arawak, Taino, Carib)were wiped out was because of the small periods of time between epidemics. In the early 16th century a lot of natives survived smallpox only to be killed soon after by measles. An earlier introduction of smallpox or a later introduction of measles would enable the natives to recover some of their population and develop immunity.
 
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