The World Has Never Eradicated a Parasite. But Jimmy Carter Is About To. (Vox)

From article:

Hopkins estimates the total cost of the three-decade [guinea worm] eradication campaign at about $350 million. Any way you slice it, that's a bargain given the amount of human suffering averted. A 2011 Center for Global Development case study pegged the cost at $5 to $8 per person treated; a 1997 analysis by the World Bank estimated that if one only considers the increase in agricultural productivity that would result from eradicating the worm (achieved by eliminating worm-related work absences), and no other potential benefits, the rate of return is 29 percent.

In other words, for every $1 invested in the campaign, $1.29 came back in the form of greater agricultural output and earnings.

Even better, the campaign comes with a number of positive externalities that help accomplish other global development tasks. There's the increase in agricultural productivity, for one thing, but additionally, researchers at the Carter Center and Emory point out that school attendance can tick up when an area is rid of guinea worm.

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