CDC links measles outbreaks in multiple states for the first time
On Monday, health officials for the first time linked the measles outbreak that began in Texas to another in Utah and Arizona, a finding that could end America’s status as a nation that has eradicated measles.
The news came in a phone call between officials at the Centers for Disease Control and Prevention and state health departments, a recording of which was obtained by The New York Times.
The chain of transmission began in January in a conservative Mennonite group on the western edge of Texas and spread to Oklahoma and New Mexico.
Countries lose their elimination status after 12 months of sustained transmission. If the outbreak cannot be suppressed by January, the anniversary of the first cases in Texas, the United States will lose the so-called “elimination status” that the World Health Organization has held for 25 years.
“I wouldn’t give the code yet, but I think the patient is not really doing well,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.
Canada lost its status last week, ending a 27-year reign after failing to control an outbreak that began at a Mennonite gathering in October 2024.
Losing elimination status may not result in tangible changes, such as travel restrictions. But experts call the possibility “deeply embarrassing” for a wealthy country with the medical resources of the United States.
“CDC and state and local health authorities continue to work together to assess transmission patterns and ensure an effective public health response – which led to the outbreak being declared over in Texas,” Andrew Nixon, a representative for the Department of Health and Human Services, wrote in a statement.
This month, the CDC submitted its outbreak information to the Pan American Health Organization. As of Nov. 13, the CDC had confirmed 1,723 measles cases nationwide, 87 percent of which were linked to a record 45 outbreaks so far this year. In 2024, however, 16 outbreaks were reported.
About 92 percent of cases reported this year involve people who are either unvaccinated or whose vaccination status is unknown.
The circulating measles subtype, identified by number 9171, first spread in Gaines County, Texas, on January 20 and is “unfortunately continuing to do so in multiple jurisdictions,” said Dr. David Sugerman, who leads the CDC’s measles response, on the call.
The country’s measles eradication status is “very much at risk if we see the same sequence being transmitted in current outbreaks lasting until the end of January,” he said, when the outbreak has already lasted a year.
The CDC is working with health authorities in Canada and Mexico to share best practices and collaborate on deciphering the genetic sequences of the measles virus, he added.
The outbreak in Utah and Arizona is currently the largest in the country, with more than 180 cases. Most new infections are among household members of infected people, but about one in four in both states have unknown origins, suggesting officials are missing some sources of exposure. About 7 percent of infections were transmitted at community events, including weddings and other celebrations.
Local health officials in Utah said efforts to promote vaccinations in the region have had a “limited” impact. While there was an initial increase in vaccination rates early in the outbreak, progress has slowed.
“It wouldn’t surprise me in the least if there was further spread in the next few months,” said Dr. David Kimberlin, who serves on an expert panel analyzing measles data for the U.S. elimination status review.
Another large outbreak at two South Carolina schools is nearing containment. Four cases have been reported in Rockland County, NY, the first since a massive outbreak in 2018 that lasted ten months. This outbreak swept through Orthodox Jewish communities, with vaccination rates in some below 70 percent.
“Overall, the risk of widespread measles transmission in the United States remains low,” said Dr. Sugerman. But the virus could spread quickly through tight-knit communities where vaccination rates are low, he warned.
The infections in New York this year can be traced back to two people who traveled from Israel. In total, there have been 152 imports from at least 47 countries in the US, including eight new ones in the last two weeks alone.
