Mapping the Worm Wars: What the Public Should Take Away from the Scientific Debate about Mass Deworming

The unique feature of that original study from Kenya, by Michael Kremer and Ted Miguel, was that it found important effects of mass deworming on school attendance — not just for children that got deworming pills, but for other kids who didn’t get the pills, both in the same school and in nearby schools. That’s plausible because the more infected kids take the pills, the less infected excrement is in the nearby environment, so it could be that fewer nearby kids who didn’t take pills get infected in the first place. This “spillover” effect to other kids would tend to magnify the pills’ impact, so Kremer and Miguel concluded that mass deworming is “far cheaper than alternative ways of boosting school participation.”