Thursday, November 12, 2009

Why cutting carbon won't stop malaria

Climate Change and Malaria in Africa
Why limiting carbon emissions won't do much to stop disease

What I find most satisfying about the AGW debate is when you don't even have to debate the climate science because the conclusions drawn are faulty even if the world does get warmer. It makes the job much easier for those of us in the skeptic-but-not-a-climatologist crowd.

If you've been following this blog you will have realised by now that misrepresentations of mosquito born disease and AGW is my own personal bugbear. Bjorn Lomberg just said something eminently reasonable in a Wall Street Journal opinion piece:

Malaria is only weakly related to temperature; it is strongly related to poverty. It has risen in sub-Saharan Africa over the past 20 years not because of global warming, but because of failing medical response. The mainstay
treatment, chloroquine, is becoming less and less effective. The malaria parasite is becoming resistant, and there is a need for new, effective combination treatments based on artemisinin, which is unfortunately about 10 times more expensive.

Yeh. What he said.

I can also add a bit more about artemisinin, or qinghaosu if you speak Mandarin. Artemisinin was isolated from Artemisia annua, or Qing Hao as it's known in much of China. It wasn't just randomnly discovered by a big pharma lab, Chinese researchers went combing through traditional materia medicae for herbs that were indicated in what was probably malarial disease.
They managed to isolate qinghaosu (artemisinin) fairly easily, worked out it was an effective antimalarial, and then spent the next 10 or so years trying to convince the academic snobs of the developed world that they weren't making it up. Conveniently for everyone involved, Artemisia annua is a weed. In the US its common name is Sweet Annie and it grows everywhere. This is important because the "herb" that is commonly prescribed along with Qing Hao in traditional Chinese Medicine for tertiary fevers is soft-shelled turtle shell. If research had gone the other way, we might really have a problem of supply.

I don't think supply of artemisin is the real issue. Apart from the issue of why pharmaceutical companies can't be arsed making it and are charging too much for what they do, the real issue is that we are going to screw up with prescribing it just the same way we have done with the other antimalarials, and it won't be effective anymore. When artemisin was first coming onto the market, everyone solemnly swore that they were going to prescribe it in combination and use it wisely to prevent malarial resistance deveoping. Then it started being sold over the counter in Thailand and Papua New Guinea, among other places, and now its already too late. The big, bad malaria, P. falciparum, is already developing resistance.

So, to my mind, what we really need to prescribe it in combination with is something like DDT. Yes, I know, I know. DDT is evil, but so was Rachael Carson, if you ask me. Personally, I would have liked to see her writing "Silent Spring" on the Thai-Cambodia border and see how she felt about DDT by the end of it. I have heard its difficult to type when you're shaking with fever and your spleen is the size of an inflatable beach ball.


  1. DDT use was stopped in Africa because it was increasingly ineffective. It's never been banned in Africa.

    Maybe Africans don't use it because they don't want to use something that is ineffective. Maybe Africans are not as dumb and inactive as you appear to think.

    Mosquitoes develop resistance to DDT more effectively than the parasites develop resistance to drugs. Biology works the same way on both sides of the vector equation.

  2. Hi Ed, you may have noticed I said "something like DDT". I'm aware of pesticide resistance. Please don't confuse a jibe directed at the work of Rachael Carson (who is fair game as far as I'm concerned) with somehow thinking an entire continent is "dumb an inactive" (methinks you have some issues, much). As someone who almost lost half her family to falciparum cerebral malaria, I'm no stranger to the disease, but lets all agree that aerial spraying ain't what it used to be.
    And please remember there is a degree of sardonic humour in everything that I post.


All comments will be moderated, so don't worry if they don't show up immediately. All comments (and offers of funding from Big Pharma or it's cousin Big Oil) are appreciated. Nigerian banks need not apply.