Malaria - Range - Global Warming

[Vexer]

How does the alleged 'Global Warming' effect the increase of the range of malaria-carrying mossies?

 

I have always heard it was temperature-related.

 

But now I've heard there have been malaria epidemics in cold-areas, such as Archangel (tundra-Russia).

 

What's the story here? Are malaria-carrying mossies temperature controlled?

 

Or?

[iNow]

What I've heard is that there is a range of temperatures in which malaria carrying mosquitos can thrive (in fact, I think it might be all mosquitos, and not just those which carry malaria). As one gets to higher elevations, the temperature tends to cool, so mosquitos cannot live there (or, more to the point, it's much more difficult for their larvae to hatch in cooler areas).

 

Humans who have moved to higher elevations did not suffer malaria as much as those who did not, because the cooler temperatures of those higher elevations prevented mosquitos from following (and ultimately biting) them.

 

With the rise in average annual global temperatures, these higher elevations are not as cool... they are warming up on average.... so these zones which were previously inhospitible to mosquitos (and mosquito reproduction) are no longer, so their range has effectively increased as a result of rising temperatures.

 

 

I cannot recall where I read this, so hopefully someone will correct me if I've mispoken.

[LookUp2]

How does the alleged 'Global Warming' effect the increase of the range of malaria-carrying mossies?

 

I have always heard it was temperature-related.

 

But now I've heard there have been malaria epidemics in cold-areas, such as Archangel (tundra-Russia).

 

What's the story here? Are malaria-carrying mossies temperature controlled?

 

Or?

From the conclusion:

"This rapid recrudescence has been attributed to population increase, forest clearance, irrigation and other agricultural activities, ecologic change, movement of people, urbanization, deterioration of public health services, resistance to insecticides and antimalarial drugs, deterioration of vector control operations, and disruptions from war, civil strife, and natural disasters. Claims that malaria resurgence is due to climate change ignore these realities and disregard history. For example, the many statements that recent climate change has caused malaria to ascend to new altitudes (10,31,32) are contradicted by records of its distribution in 1880 to 1945"

 

http://www.cdc.gov/Ncidod/eid/vol6no1/reiter.htm

 

Another expert commentary on 'increased disease':

http://www.smh.com.au/news/opinion/rise-of-deadly-disease-is-a-cultural-thing/2005/10/16/1129401141539.html

 

"Microbes, like us, are evolutionarily programmed to survive, and they have had long practice. If, in today's increasingly interconnected world with its many vulnerable populations, we further disturb natural environmental systems and distort long-established cultural constraints, then the procession of new infectious diseases will continue."

 

Tiger mosquitos (I think thats the one) which carry a type of encephilitis, were imported to the USA from Japan (or somewhere nearby) in cargo containers. The specie has flourished and spread.

 

http://ohioline.osu.edu/hyg-fact/2000/2148.html

 

So anyways, the point being one cannot assign blame to warming alone, and its is just as likely warming has limited, and possibly no impact on the incidence of malaria.

[iNow]

So anyways, the point being one cannot assign blame to warming alone, and its is just as likely warming has limited, and possibly no impact on the incidence of malaria.

 

I agree with your point that blame to warming alone would be in err, but I've already shown at least one impact of warming on this issue so your second comment regarding the possible lack of any impact whatsoever is not accurate.

[LookUp2]

I agree with your point that blame to warming alone would be in err, but I've already shown at least one impact of warming on this issue so your second comment regarding the possible lack of any impact whatsoever is not accurate.

 

First, I would point out my first link directly addressed the OP query "What's the story here? Are malaria-carrying mossies temperature controlled?".

 

I am just guessing here, but would say your response directed to me indicates you did not bother to read the first link, as it addresses malaria outbreaks in non-tropical (and pretty darn cold) regions.

 

Now to address your contention that warming increases malaria events I would point you to these two abstracts (and there are others out there you can search for yourself) which state "These findings are most relevant to regions near the altitude or latitude limits of the disease, where several epidemics have lately been reported."

http://www.ncbi.nlm.nih.gov/pubmed/7907685?dopt=Abstract

The above link does not claim the ranges of malaria laden mosquitos has increased in altitude, only that more incidence is occuring at the higher end of their known range. Its too bad that so many of these reports are hidden from view behind pay-per-view accounts. What we do not know is whether the number of people has increased in these higher altitudes, what deforestation has occured and the other factors which lead to higher transmission rates regardless of temperatures.

 

Therefore, the temperature increase of 0.5 degree C during the last 2 decades cannot be incriminated as a major cause for these malaria changes, which are mainly due to the combination of climatic, human, and operational factors.

http://www.ncbi.nlm.nih.gov/pubmed/9673911?dopt=Abstract

 

The second link I posted introduced the viability of micro-organisms to adapt to their environments and are complimented by human travel, proximity and a host of other factors that increase the chances of a microbe advancing its pool of hosts.

 

The third link I posted presented the exotic introduction of a known transmitter of a host of human diseases, the tiger mosquito, a particular favorite of mine after a friends kid became infected with encephalitis. He survived as do the tiger mosquitos with their inherent capability to transmit a multitude of diseases to humans and animals.

 

http://www.vet.uga.edu/vpp/clerk/jennings/index.php

[iNow]

Excellent. I think you misunderstood my point, but that's not really relevant. You've done a great job addressing the OP.

[Vexer]

High quality responses. I didn't really expect that.

 

My take-home message is that: Claims that malaria resurgence is due to climate change ignore these realities and disregard history.

[iNow]

High quality responses. I didn't really expect that.

 

My take-home message is that: Claims that malaria resurgence is due to climate change ignore these realities and disregard history.

 

Except, I'd update that to say, "Claims that malaria resurgence is due ONLY to climate change ignore these realities and disregard history."

 

Again, as I've shown, climate change impacts the regions where mosquito larvae can thrive, which is in warmer climates.

[LookUp2]

High quality responses. I didn't really expect that.

 

My take-home message is that: Claims that malaria resurgence is due to climate change ignore these realities and disregard history.

 

Yes. Human travel, living, medical, political, and cultural changes have had the greatest impact on increasing (or decreasing) malaria transmission rates.

 

Interesting article about Canadian malaria outbreaks:

http://www.cdc.gov/ncidod/eid/vol10no7/03-0826.htm

The above points out the methods of tracking travelers has a hole in the monitoring system, but makes good points about particular outbreaks in India and their connection to N. American outbreaks.

 

Heres a 1948 article about US Malaria:

http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=1624804&pageindex=1#page

 

Related to a microbe (in this case virus) ability to adapt to a new environment, Saskatchewan:

"West Nile virus (WN) is a virus of wild birds, transmitted from bird to bird primarily by mosquitoes. Native to southern Europe, the Middle East and Africa, the virus arrived in North America in 1999 and spread quickly across the continent."

http://wildlife1.usask.ca/wildlife_health_topics/arbovirus/WNV%20and%20mosquitoes%20in%20SK%20P%20Curry%20Blue%20Jay%20June%2004.pdf

[Vexer]

That was really interesting. Hm.