It’s been a year since a measles outbreak began in West Texas, and international health authorities say they will meet in April to determine whether the U.S. has lost its status as a measles-free country.
Experts fear that the vaccine-preventable virus has regained its foothold and that the US will soon follow Canada and lose the achievement of eliminating the virus.
The reevaluation is largely symbolic and would be based on whether a single measles chain has spread continuously in the US for at least 12 months.
Public health scientists across the country are investigating whether the now-ended outbreak in Texas is linked to active outbreaks in Utah, Arizona and South Carolina.
But doctors and scientists say the US and North America in general have a measles problem regardless of the decision.
“It’s really a matter of semantics,” says Jonathan Temte, MD, PhD, a Wisconsin family physician who helped determine that the U.S. was measles-free in 2000.
“The bottom line is that the conditions are sufficient to allow for as many cases to occur. And that in turn comes down to de-emphasizing a safe and effective vaccine,” he added.
Last year, the CDC confirmed 2,144 cases of measles in 44 states, the most since 1991, and nearly 50 separate outbreaks.
“The most important thing we can do is make sure that the people who aren’t vaccinated get vaccinated,” said Jennifer Nuzzo, DrPH, director of Brown University’s Pandemic Center. “We have not yet given a clear enough message about this.”
There is little room for error when trying to stop measles. The virus is one of the most contagious, infecting nine out of 10 unvaccinated people exposed to it.
The patient in Texas’ first known case developed the rash on Jan. 20, 2025, according to state health department data.
From that moment on, the outbreak exploded. Officially, 762 people fell ill, most in rural Gaines County, and two children died.
Scientists have confirmed the same measles strain in Texas, New Mexico, Utah, Arizona, South Carolina, Canada, Mexico and several other North American countries, said Sebastian Oliel, a spokesman for PAHO, which will make the final decision on U.S. measles eradication on April 13.
Oliel said that when there is a case of unknown origin in a country with persistent local spread, “the most conservative approach is to consider the case as part of existing national transmission.”
