Medieval (12th century) outbreak of mystery disease (malaria ?)

[rosesnake]

Already searched : “medieval illness/disease”, “medieval  epidemics”, “epidemics”, etc + the various diseases that presented  themselves during those searches but without much success for my  specific set of requirements. So I turn to you lovely people for help  ...

Setting : Medieval (late 12th century) - Middle east (present day Lebanon) in a

Comments

[hhimring]

I guess for malaria you'd need swampy conditions somewhere close and a reason why breeding conditions were especially good for the mosquitoes that year (more rainfall?).

Medieval descriptions of such things in western chronicles can be rather unspecific, in that period; they tend to just mention pestilence or the like.

Other internet searches that could possibly throw something up something useful: illness and the Second and Third Crusades (approximately contemporary and I seem to remember there was illness among the crusaders), early Arabic medicine.

[laridian]

There are also many "mystery" outbreaks that have never been resolved, such as Picardy sweats, English sweating sickness, etc. If all else fails, make something up that fits what you have. The people of that time certainly won't know what it is and will give it some name that "seems right".

https://en.wikipedia.org/wiki/Category:Ailments_of_unknown_cause

[sollersuk]

And there's also the fact that diseases change. wasWhen I was very small, scarlet fever was a highly infectious, dangerous killer (it was what fever hospitals were built for). By the time I was in secondary school it was just another childhood illness, less nasty than some. This gives even more scope.

[laridian]

Better example: syphilis.

During its first recorded European outbreak (Naples, 1490s) it was contagious, swift-acting, painful, disfiguring, and 100% lethal.

By 1750, it was remained contagious (still is today), but symptoms might take weeks - even months - to appear and a healthy younger person might live years (or even a decade).

How much of this is due to weakening of the disease and how much to Darwinian pruning of the less-resistant population is left as an exercise for the reader.

[anonymous]

Malaria is not a problem in Lebanon because there aren't enough mosquitoes to transmit it; it's not a tropical clime. I would just choose a disease which has been eliminated by modern vaccines, such as polio, which is resurging in Syria due to the war and broken infrastructure and which may resurge in the US due to stupidity lol.

Am Syrian and Lebanese (and a medic).

[haldane]

Have you considered the great classic, bubonic plague?

[sollersuk]

Your third criterion is tricky. If a disease is around at a low level, the population can build up a level of immunity and you don't get sudden catastrophic outbreaks. Bubonic plague did have major outbreaks, apparently triggered by population increase of rodents on the steppes, but nothing low-level in between.

You also appear to need an animal vector, as in malaria, bubonic plague and avian flu. The problem here is that they tend to spread geographically quickly and easily; on several occasions bubonic plague spread across the whole of Europe within a few years as the vectors travelled or were taken, and malaria was found in marshy areas even in Britain until quite recently. If avian flu gets into the wild bird population it will be impossible to control.