The Pattern
Across decades and countries, measles is consistently the first disease to resurge when vaccination coverage drops.
This is not coincidence.
What Makes Measles Different
- Airborne transmission
- Extremely high contagiousness
- Short exposure time required
- High immunity threshold
Why Small Changes Matter
- Minor coverage drops enable outbreaks
- Clusters amplify transmission
- Travel spreads infection quickly
Herd Immunity Thresholds
Most infections tolerate partial immunity.
Measles does not.
When population immunity falls even slightly below required thresholds, outbreaks occur rapidly and visibly.
Why This Matters in 2026
Policy language often changes before behavior does — but behavior changes before data catches up.
Measles acts as an early signal that protection levels are slipping.
Key Takeaway
Measles resurgence is not a failure of modern medicine.
It is a predictable response to reduced immunity.