# Measles is back in the United States, WHO authorities say

Source: [Latest from Live Science in Health](https://www.livescience.com/health/viruses-infections-disease/measles-is-back-in-the-united-states-who-authorities-say) · 2026-11-14 · Medicine
Page: https://themorning.science/story/measles-is-back-in-the-united-states-who-authorities-say-f1ed80b60b3d0495
Kind: other · Impact: medium

## In brief

- WHO authorities say measles is officially back in the United States.
- The U.S. had eliminated measles in 2000, meaning no continuous domestic spread for over a year at that time.
- The country had been free of the disease for more than 25 years before this determination.

## Why it matters

Loss of measles elimination status signals sustained domestic transmission and waning population immunity, which affects public health planning and vaccination coverage assessments.

## Timeline

- 2000-01-01: U.S. officially eliminated measles, meaning over a year without continuous domestic spread
- 2026-11-14: WHO authorities state measles is officially back in the United States

## Coverage

- [Measles is back in the United States, WHO authorities say](https://www.livescience.com/health/viruses-infections-disease/measles-is-back-in-the-united-states-who-authorities-say) — Latest from Live Science in Health, 2026-11-14

Tags: measles, public health, vaccination, elimination status, who

---

Brief generated by AI (claude-haiku-5-5) from the reporting listed under Coverage. Headlines belong to their publishers. The Morning Science – https://themorning.science