Alternate Malarial Zones

I've been thinking about malaria and the lack of it. Specifically, I've been thinking about Charles Mann's 1493 and what he wrote about southeastern England becoming malarial when swamps were partly drained. Earlier, the swamps were regularly washed by salt water which came in during high tide and killed off mosquito larvae. When partially drained, the swamps got separated from the sea and so mosquito populations boomed, and malaria became endemic in England during Shakespeare's time.

Now, I wonder what could change to allow for malarial zones to shrink or grow in certain areas of the world. Human activity or very mild geological POD's could drastically change where malaria occurs. For example, I was thinking that in the southeastern United States where malaria was a major problem, and slowed down European settlement. However, what if you got a stretch of coastline where there were semi-saltwater swamps, which acted as a malarial prophylactic-and some Europeans settled near it, but managed to avoid destroying it? It could create a gateway to the interior, speeding up European settlement in the area and, potentially, give a nation other than England an early edge in North America.

Anyone have any other thoughts how changes in malarial zones could be achieved, and where?
 
The thing is that malaria parasites need a temperature of 15c or more to develop. If the temperature drops below that, they wont. So, theres a couple of months a year when malaria can breed in England, but it would have to be reintroduced every year.

Note that the high veldt of zimbabwe is malaria free, and its climate is subtropical ... it dips below the critical temperature occasionally, tho, so malaria is not endemic.
 
A volcanic eruption could cool a climate, or a meteorite could alter a coastline. Would Spanish Florida have had malarial problems preventing further colonization?
 

katchen

Banned
For that we can thank Captain Arthur Phillip (Commander of the 1788 First Fleet) and subsequent Governors of Australia for refusing to permit the introduction of African slaves (who carried falciparum in their bloodstreams) into Australia.
Any one of the West Indies would have remained Malaria (and Yellow Fever) free if it had been settled exclusively by Europeans and African slavery prohibited.
 
For that we can thank Captain Arthur Phillip (Commander of the 1788 First Fleet) and subsequent Governors of Australia for refusing to permit the introduction of African slaves (who carried falciparum in their bloodstreams) into Australia.
Any one of the West Indies would have remained Malaria (and Yellow Fever) free if it had been settled exclusively by Europeans and African slavery prohibited.

well, here is one way, tied to an idea of a thread - what if slavery in Australia...

Is there a ressource at least in Australia that slave labour would have made VERY (or more) profitable, or would have motived pushing for the costly 'imports'? Would earlier discovery of coal, mining for it do - I heard it 'made' Sydney.

(Of course, the poor slaves are not to be blamed for this, but slavists. They didn't after all asked to leave Africa.)
 
According to Jared, malaria is already endemic to Australia but it's not a very dangerous species. A wetter Australia could have it spreading further, but it doesn't guarantee that falciparum gets established.

Falciparum malaria was established in northern Australia - probably before European contact - until eradicated in 1981.

What was different is the mosquitoes which spread malaria in Australia (of the Anopheles genus) are much less efficient at it. They don't live that long, and they also preferentially bite other mammal species (especially dogs) over humans.

A wetter Australia wouldn't change much in itself. There's a line in Australia (roughly at 19 degrees of latitude south) which is the danger zone for infection, due to the activity of mosquitoes etc.

A warmer Australia would change that, though. One of the current consequences of climate change is that this line is moving south. It's not yet a problem for malaria - which is eradicated, barring traveller-borne cases - but is causing the southward spread of other mosquito-borne diseases such as Ross River fever.

For that we can thank Captain Arthur Phillip (Commander of the 1788 First Fleet) and subsequent Governors of Australia for refusing to permit the introduction of African slaves (who carried falciparum in their bloodstreams) into Australia.
Any one of the West Indies would have remained Malaria (and Yellow Fever) free if it had been settled exclusively by Europeans and African slavery prohibited.

For the reasons I outlined above, yellow fever would only be a problem in northern Australia, if established. Same as Ross River fever is currently, and malaria was.

There are many reasons to be thankful that official slavery was never established in Australia - though unofficial slavery was, in northern Queensland - but those reasons aren't closely linked to yellow fever or malaria.
 
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