Second-Order Wins✓✓ 3 independent sources
Pennies-a-Dose Pills, Decades of Paychecks
+17% hours worked a decade later; 32% annualized return
Miguel & Kremer's landmark randomized trial found school-based mass deworming cut absenteeism by one quarter, with health spillovers onto untreated children. The decade-later follow-up (Baird et al., QJE 2016) found men who were treated as boys working 17% more hours, women 25% likelier to reach secondary school, and a 32% annualized return — while evidence from America's hookworm-eradication era points the same way: treating childhood disease pays lifetime dividends.
Deworming children in Kenya cost pennies per dose — ten years later, treated men worked 17% more hours each week and the program returned 32% a year.
The receipts
- The Quarterly Journal of Economics: Worms at Work: Long-run Impacts of a Child Health Investment (Baird, Hicks, Kremer & Miguel)
- NBER: Worms: Identifying Impacts on Education and Health in the Presence of Treatment Externalities (Miguel & Kremer)
- The Quarterly Journal of Economics: Disease and Development: Evidence from Hookworm Eradication in the American South (Bleakley)