Capitalism can cause malaria
I want to focus on one line from MacAskill's article. Addressing the popular and cost-effective charitable cause of malaria eradication, he says "Capitalism doesn’t cause malaria. Mosquitoes do." I think a little political ecology knowledge will show that capitalism does in fact cause malaria -- or at least capitalism significantly shapes the prevalence of malaria.
The immediate cause of malaria, of course, is actually the Plasmodium protozoan. Plasmodium is transmitted by mosquitoes. Those mosquitoes breed in shallow, stagnant water in warm climates. Capitalism can affect all of these steps.
The most immediate effect -- and probably closest to the kind of thing that Buffett had in mind -- is that capitalism shapes what livelihood opportunities are available to people in malaria-heavy regions, and thus how well people are able to afford their own malaria treatments. After all, it's not as if the Gates Foundation is the world's only source of chemically treated bed nets or malaria drugs. If capitalism produces economic inequality -- and there's good reason to think that the current system does so for many poor rural people in malaria-heavy regions -- then capitalism is creating the malaria risks that its leaders are paying to eradicate.
Capitalism also has effects on the presence of mosquito breeding conditions. Capitalism shifts people's livelihood strategies, for the most part away from subsistence farming and toward a limited suite of cash crops, urban employment, and tourism schemes. The precise effects of these changes will vary from place to place. But in some areas the resulting changes in land use can increase the presence of mosquito breeding grounds -- and in turn the risk of malaria. Capitalism also drove the widespread agricultural use of DDT, which in turn caused the evolution of DDT resistance in mosquitoes, undercutting the effectiveness of targeted DDT use in malaria eradication.
Capitalism is also a driving force behind climate change. Whether or not you think some form of "green capitalism" is possible, to date capitalism has driven massive expansions of fossil fuel use and methane-generating agriculture. Climate change, in turn, is expected to expand the range of malaria.
My point here is not simply capitalism-bashing. In some cases capitalism can reduce the prevalence of malaria independent of any philanthropy. Capitalism has certainly made mass-production of malaria treatments like bed nets and drugs possible. And in some cases, capitalism-driven development reduces mosquito breeding conditions -- consider the eradication of malaria from the US South through swamp drainage. The point, rather, is that social systems such as the economic structure of capitalism are implicated even in seemingly apolitical issues like malaria. Always be skeptical if someone claims that capitalism has nothing to do with some problem.