Hello historians,
What are some interventions before 1920 that improved human well-being 100 years later?
For examples:
- Holden Karnofsky cited United States Hookworm reduction starting around 1909.
https://www.openphilanthropy.org/research/philanthropys-success-stories/
https://en.wikipedia.org/wiki/Hookworm_infection#Eradication_programmes
- Jason Crawford cited Smallpox inoculation before 1700 and vaccination starting around 1796.
https://rootsofprogress.org/smallpox-and-vaccines
The example of rabies inspired a search for leading causes of death in the 1800s. Here's one article that sounded plausible for 1850 and 1900: https://nonprofitupdate.info/2010/10/21/10-leading-causes-of-death-in-1850-and-2000-2/
Another plausible stat from the United States from 1900 follows:
https://www.statista.com/statistics/235703/major-causes-of-death-in-the-us/
Prevention of a frequent cause of death from 1900 (such as pneumonia, tuberculosis, and diarrhea) sounds like a plausible clue to identifying an intervention that benefited many humans by 2020. One example that comes to mind from GiveWell's recent grant to Dispensers for Safe Water is water chlorination.
https://blog.givewell.org/2022/04/06/water-quality-overview/
Wikipedia claimed chlorination spread in the United States in the early 1900s.
https://en.wikipedia.org/wiki/Water_chlorination