|March 2nd, 2012|
Dr. Farmer's answer was that in order to solve the problems of the developing world and break the cycle of poverty you can't just do one thing, no matter how cost effective it is. If all you're doing is distributing mosquito nets, what are you going to do if someone comes to you with a broken arm? What about AIDS? Clean water?
He is an expert in this field, and I have a lot of respect for him, but I don't think he's right here. No matter what intervention or combination of interventions you choose, you're not going to help everyone. When you build full hospitals you can provide very good care to some people, but others who are too far away or beyond the capacity of your hospital will have the same low quality options as before. A committment to provide first-world care, to the extent that you include expensive treatments, is a committment to helping fewer people.
At any level of funding below "full global healthcare system", choosing to do something other than the most cost effective interventions  means more people suffering and dying.
 In terms of cost per death averted, QALY/DALY, or whatever metric you want. Any reasonable choice here puts mosquito nets above anti-retroviral therapy and them both well above training seeing-eye dogs. Cost effectiveness is not limited to medical interventions, though they are easier to evaluate: public health, education, road building, (conditional) cash transfers, and job creation also have positive effects and we do best to work on whichever has the best marginal impact.