U.S. No Longer Meets Measles Elimination Standard After 26 Years

WHO:

The Washington Post - International health experts determined that the United States no longer met the standard for eliminating continuous measles spread; the announcement was pending.

CNN - An independent commission reporting to the director of the Pan American Health Organization (PAHO) made the determination, according to a source close to the process.

CNN - Dr. Angela Rasmussen, a virologist at the University of Saskatchewan and editor-in-chief of *Vaccine*, said Utah’s data alone would have supported the decision.

CNN - Dr. Demetre Daskalakis, former director of the CDC’s National Center for Immunization and Respiratory Diseases, said elimination status is “a vital sign for our public health system.”

CNN - Dr. Nuwan Gunawardhana of Columbia University Irvine Medical Center called the loss “so devastating and so sad.”

CNN - Dr. William Moss, a Johns Hopkins Bloomberg School of Public Health professor and measles expert, described measles complications and their risks.

CNN - Dr. Peter Hotez, co-director of the Center for Vaccine Development at Texas Children’s Hospital, called the loss “incredibly embarrassing” and said, “Basically, measles is back.”

WHAT:

The Washington Post - The United States lost its status as a country that had eliminated continuous measles transmission.

CNN - Measles had been considered eliminated as a continuously transmitting illness in the United States since 2000.

CNN - More than 5,400 U.S. measles cases were reported in 2026, the highest number since 1991; 43 new outbreaks were reported, and more than 1,000 cases were linked to outbreaks that began in 2025.

CNN - Nearly all reported cases in 2026 involved people who were unvaccinated or whose vaccination status was unknown. About 1 in 9 reported cases resulted in hospitalization; state reports recorded at least 10 deaths.

CNN - Two MMR vaccine doses reduce an exposed person’s chance of getting measles by 97% compared with no vaccination.

CNN - Measles can cause fever and rash, erase immune memory, lead to secondary infections, infect a baby before birth, and rarely cause fatal subacute sclerosing panencephalitis (SSPE).

WHERE:

CNN - Utah researchers reported sustained transmission in the state; outbreaks also occurred in South Carolina, Pennsylvania, Wisconsin and New York.

CNN - Canada lost its elimination status after an outbreak across several provinces; Mexico was also at risk of losing its status.

WHEN:

CNN - The United States had maintained measles elimination status for 26 years.

CNN - A Utah preprint published in August found the same strain circulating for more than a year, causing over 600 cases between June 2025 and June 2026.

WHY:

CNN - Falling vaccination levels and rising case counts contributed to sustained transmission; in 2025 and 2026, the virus reached more unvaccinated families and communities.

HOW:

CNN - The committee assesses endemic transmission by determining whether the same strain passes person to person within a country for at least a year, using genetic codes from patient virus samples.

CNN - Measles is airborne; one infected person typically infects 12 to 18 others, and the virus can remain in a room for hours.

(UPDATED November 14, 2026 09:59 UTC)

The United States has lost its measles elimination status after sustained transmission. Cases have surged to their highest level since 1991. Falling vaccination rates helped fuel outbreaks, mostly among unvaccinated people.