Until this year, public-health officials have abided by a simple playbook for measles outbreaks: Get unvaccinated people vaccinated, as quickly as possible. The measles component of the measles, mumps, and rubella shot that nearly all American kids receive today is “one of the best vaccines we have,” William Moss, a measles expert at Johns Hopkins Bloomberg School of Public Health, told me. Two doses in early childhood are enough to cut someone’s risk of getting measles by 97 percent. And vaccination is the only surefire way to slow the spread of the wildly contagious disease.
In the weeks since a measles outbreak began in West Texas and spilled into neighboring New Mexico, local health departments have run that play, scrambling to set up free vaccination clinics. The federal government, though, appears to be writing its own rules for the game. The epidemic has already surpassed 200 known cases. But that’s likely a drastic undercount, experts told me. And it appears to have claimed at least two lives, including that of a six-year-old unvaccinated child. And yet, the CDC waited to release its first statement on the outbreak until a month or so after the epidemic began, and even then, it didn’t directly urge parents to get their kids up-to-date on MMR shots.
More recently, the Department of Health and Human Services has called for doses of the vaccine to be shipped to Texas; at the same time, HHS is working on dispatching vitamin A to the region, and the department’s new secretary, Robert F. Kennedy Jr., is overinflating the importance of those supplements in managing measles. In some parts of Texas, vitamin-A-rich cod-liver oil is flying off shelves, while some parents are doubling down on their hesitations over vaccines.
When reached for comment, an HHS spokesperson noted that the “CDC recommends vaccination as the best protection against measles infections,” but added that “Secretary Kennedy and HHS are committed to aggressively handling the measles outbreak with a comprehensive, all-of-the-above approach to do what we can to save lives.”
The United States has long had small groups of people who have opted out of vaccination, but in this outbreak, the first major one of Trump’s second term, the fracture between the unvaccinated and the worried well is looking especially stark. Many of the people most eager to get a shot are the ones who need it least: young, healthy individuals nowhere near a detected outbreak, who already have all the MMR doses they’ll likely ever need. Meanwhile, those who would most benefit from vaccination have been pointedly reminded that doing so is a personal decision, as Kennedy has put it—a framing that could add to the growing death toll.
Before the 1960s, when the measles vaccine became available in the U.S., the virus infected roughly 3 to 4 million Americans each year. In most cases, the disease would resolve after a few days of cough, fever, and a telltale rash. But measles can also quickly turn dangerous, causing complications as severe as pneumonia and brain swelling. Researchers have estimated that the virus can infect 90 percent of the unimmunized people it comes into close contact with, and roughly one out of every 1,000 cases will result in death. One study found that, in the era before the vaccine, up to half of all infectious-disease deaths in kids might have been caused by measles. Those who survive the disease are sometimes left with permanent brain damage; the virus can also warp the immune system, wiping out the body’s memory of past infections and vaccines, which leaves people more vulnerable to disease.
In the U.S., getting measles as a child—and risking all of those horrors—was once considered a grim matter of course. Decades of vaccination helped the U.S. eliminate measles by the year 2000 and keep the virus mostly at bay since then. But the cracks in that wall have been widening. For a virus as contagious as measles, vaccine coverage needs to remain above 95 percent to prevent outbreaks. A drop of even just a couple of percentage points in immunization can double the virus’s attack rate, Mark Jit, an epidemiologist at New York University, told me. In many parts of the U.S., that’s now a real threat: Nationwide, less than 93 percent of kindergartners were fully vaccinated against measles for the 2023–24 school year. Unvaccinated and undervaccinated people also tend to cluster; the outbreak in West Texas, for instance, has hit particularly hard in Gaines County, which is home to a Mennonite community wary of the health-care system, and which has a kindergarten-vaccination rate of just 82 percent.
Vaccine-uptake rates in the region appear to have risen in the weeks since the outbreak began. But several experts told me they were disturbed by the lack of strong, consistent messaging from federal leadership. In the past, outbreaks have prompted immediate vaccine advocacy from the federal government: During a 2018–19 measles outbreak clustered in an Orthodox Jewish community in New York, the CDC director, Robert Redfield, and HHS secretary, Alex Azar, issued joint statements emphasizing the importance of vaccination. Redfield called on health-care providers to “assure patients about the efficacy and safety of the measles vaccine”; Azar stressed that the safety of the shots “has been firmly established over many years in some of the largest vaccine studies ever undertaken.”
People aren’t necessarily taking their first cues from federal appointees. Studies show that health-care-provider recommendations are a major factor in people’s decisions about vaccination. But national messages can still cue local health officials and physicians to double down on their efforts, Robert Bednarczyk, an epidemiologist at Emory University, told me. And some of the most powerful health partnerships can involve community leaders with cachet among families. During the 2018–19 measles outbreak, public-health officials made “deliberate attempts to work with religious leaders,” whose recommendations would be trusted, Moss told me. Those efforts seem lacking in this current outbreak: One pastor in Seminole, Texas, told the Associated Press that he hadn’t received any direct outreach from public-health officials, and wasn’t engaging with parents in his congregation about vaccines.
A statement from HHS released this week did give some emphasis to the potency of measles shots. But it also continued to echo Kennedy’s constant praise of vitamin A as a top-line method to manage the virus, a statement now also highlighted on the CDC website. Vitamin A deficiency can worsen a case of measles that has already begun—but those deficiencies are estimated to affect less than 1 percent of Americans. Kennedy has also called out steroids and antibiotics as measles-fighting tactics, but those interventions, too, are more geared toward reducing the severity of disease once it’s already set in. “The vaccine is the only thing that stops people from getting infected,” Jit told me. And casting supplements and drugs as comparable to, or even preferable to, prevention is especially dangerous for a disease that has no cure or antivirals.
When vaccination is framed as just one option among many, parents might think twice about opting into a shot for their kid, Rupali Limaye, a health-communications scholar at George Mason University, told me. Kennedy has also framed vaccination as a personal choice, and something about which parents should “consult with their healthcare providers to understand their options”—all couches, Limaye told me, that make doing nothing an especially convenient option. “That, to me, is automatically going to lead to more morbidity and more mortality,” she said.
Meanwhile, primary-care physicians such as Sarah Turner of Lutheran Health Physicians, in Indiana, are getting frantic questions from patients who are asking if they need boosters or early shots for their infants, not yet old enough for their first MMR. Although some people, those born before 1989, may have received only one dose of MMR in childhood and be eligible for another, in most instances, the answer to those questions is usually no—especially if local cases haven’t been detected and a family isn’t planning to travel into an area where measles is rampant, Turner told me. Protection from the vaccine is thought to last for decades, maybe even an entire lifetime, in most people: “If you have two doses of measles vaccine, you don’t have anything to worry about,” Shelly Bolotin, an epidemiologist at the University of Toronto, told me.
These misalignments are a pattern in the U.S.’s reaction to infectious disease. During the worst days of COVID, too, politicians hocked dubious treatments for the virus, and anti-vaccine sentiment roiled in underimmunized communities, while some of the worried well sought out extra shots before it was clear they needed them. More recently, when mpox cases began to explode in the United States in 2022, a broad swath of Americans clamored for shots—even though the outbreak was, from the start, concentrated among men who have sex with men, who didn’t receive focused resources for weeks. And as H5N1 cases in the U.S. have risen over the past year, public worry has concentrated on the safety of pasteurized dairy products, rather than the real risks to dairy and poultry workers.
Measles is not a forgiving virus. It moves so quickly that it can capitalize on any defensive wobbles or holes in protection. As childhood-vaccination rates continue to lag and the nation’s leaders continue to dismiss data and undermine scientific rigor, experts worry that outbreaks such as these—and the country’s muddled responses to them—will become a deadly norm. Global rates of measles are rising, giving the virus more opportunities to slip into the United States. At the same time, the percentage of American children potentially susceptible to measles has grown in recent years, Bednarczyk’s research has shown. When more sparks hit more kindling, conflagrations will grow. Just over two months into 2025, the U.S. has already logged more than 150 measles cases—more than half of the total cases documented in all of 2024. If the U.S. has any hope of containing this crisis—and the ones that will surely follow—it’ll have to succeed at concentrating its resources on those most at risk.
