Vaccine researchers have long noted that preventative medicine can become a victim of its own success.
Adoption of the first vaccine for a serious disease is typically fast and widespread, driving rates of illness down dramatically with the consequences of the disease receding from public memory. Public attention shifts to vaccine safety issues—sometimes real but more often focusing on perceived dangers—and immunization rates fall. The decline precipitates a resurgence in disease, which in turn leads more people to get vaccinated. And unless the disease is eradicated, the cycle continues.
“People embraced vaccines because they were scared of the diseases,” says Dr. Paul Offit, the director of the Vaccine Education Center at the Children’s Hospital of Philadelphia. The modern information environment and the elevation of anti-vaccine activism have further compounded the dynamic. Offit and many of his colleagues working in public health fear only more disease and death will arrest the decline in vaccination rates the United States and other developed nations have experienced over the last decade.
If Robert F. Kennedy Jr. is the leader of the modern anti-vaccine movement, Offit could be considered something of his opposite. A pediatrician, co-inventor of the rotavirus vaccine, and prolific author on the history of vaccines and the falsehoods of the anti-vaccine movement, he’s watched the vaccine debate go through different iterations for decades. His work has resulted in personal attacks by anti-vaccine activists, including Kennedy and celebrities like Jenny McCarthy. (He’s also received a series of death threats.)
Offit dates the start of the modern anti-vaccine movement to the 1980s, and he faults established news outlets like ABC and NBC for elevating claims that vaccines caused brain damage and other conditions, assertions that were soon disproven by a mountain of research and studies. He criticized the bias toward “balance” as an inappropriate frame for questions involving vaccine science, citing programs like the 1982 DPT: Vaccine Roulette, a documentary aired on NBC stations. “When the media carries a story about a vaccine fear that has really been substantially answered by published studies, you can choose perspective rather than balance,” he said. By the late 2000s, many anti-vaccine voices and groups had started to lose some of their public credibility in the media. “Maybe we’re finally getting tired of putting our children at unnecessary risk,” Offit suggested in a 2014 foreword to his book Deadly Choices, which traced the history and claims of anti-vaccine groups over the previous three decades.
“If there were three cases of paralysis from polio, I think that would cause a major uproar in this country.”
Dr. Paul Offit
But these days, he strikes a more pessimistic tone. When asked what it would take to increase vaccine uptake today, Offit said a resurgence of vaccine-preventable disease will likely be necessary. He recalled a conversation he had with eminent vaccinologist Maurice Hilleman just months before his death in 2005. Hilleman was a giant of vaccine science who developed the modern measles vaccine and the measles, mumps, and rubella (MMR) combination vaccine, and he lived to see health authorities declare measles eliminated in the U.S. in 2000.
“I asked him that question, ‘Can we educate people about how serious this disease is, how important this vaccine is, or do we have to see the disease come back? Is it only the disease that’s going to be doing the educating?’” Offit told The Dispatch. “He said, ‘Yes, I think the disease has to come back,’ which was an enormous defeat for him as the inventor of the vaccine.”
Another vaccine luminary, Stanley Plotkin has recently voiced the same view in interviews with Stat published earlier this month. The 93-year old literally wrote the textbook on vaccines, which is now in its eighth edition (Offit has been a co-author and editor of the last several editions).
“The only thing that might change things would be outbreaks of diseases that could have been preventable,” Plotkin said. “But it will take a while, and so I am not optimistic that things will change in any favorable direction in the foreseeable future.”
“All I can say is that I’m beginning to regret having lived so long—because we’re going downhill,” he added.
There have been 14 new measles outbreaks so far in 2026. The spread has been fueled by the proliferation of counties with vaccination rates too low to prevent the spread of one of the most contagious diseases on the planet. Cases are approaching 1,500 and are on track to soon exceed 2025’s nearly 2,300, which marked the highest annual total in more than 30 years.
The share of Americans receiving vaccinations for diseases like measles has continued to decline in recent years. An overwhelming majority of people still get most recommended immunizations and believe in the efficacy of the MMR vaccine, but the COVID pandemic interrupted routine shots for many children and supercharged distrust in the public health establishment. Before the pandemic, 50 percent of U.S. counties had kindergarten vaccination rates high enough to sustain herd immunity, but that has since fallen to just 28 percent, according to a Washington Post analysis of state and Centers for Disease Control and Prevention (CDC) data. A January survey and modeling report by vaccine researchers suggested rates could be even lower in many counties when taking into account people often missed in data from schools and health care providers, including homeschooled students, uninsured people, and foreign-born populations.
Offit isn’t convinced resurgent measles will be enough of a jolt to the system. “People are not so scared of measles, even though measles can cause encephalitis and consequent blindness and deafness, it could cause severe pneumonia and fatal pneumonia. They see it as fever or rash,” he said. Measles is always the first disease to come back when vaccination rates slip, but Offit pointed to more frightening diseases that can return when vaccination rates fall. “Let there be a couple cases of paralytic polio, or a few children die of diphtheria or Hib [Haemophilus influenzae type b], which can cause epiglottitis and meningitis,” he noted. “If there were three cases of paralysis from polio, I think that would cause a major uproar in this country.”
The current public response to disease outbreaks is also missing key elements that have driven up vaccination rates in the past: a vocal campaign from federal authorities encouraging vaccination and state policymakers tightening vaccine requirements. Amid previous disease outbreaks, the CDC offered clear guidance on the importance of vaccination, a message that has not only been absent under Kennedy’s leadership of Health and Human Services (HHS) but actively distorted and suppressed. Kennedy’s unilateral shift from routine recommendation of many vaccines to “shared-clinical decision making”—a designation many doctors and patients take to mean optional—has left many people confused.
State lawmakers have also previously responded with more stringent vaccine requirements for schools and day care. After the 2014-15 measles outbreak in Southern California, the state cracked down on counties with low vaccination rates by eliminating parents’ ability to claim exemptions from school vaccine requirements due to personal beliefs. In the space of two years, the schools and counties with the lowest immunization rates and ardent vaccine-skeptical communities jumped from a 60 percent vaccination rate to nearly 90 percent. New York City responded to a large 2018-19 measles outbreak by mandating vaccination under penalty of fines for everyone who lived and worked in parts of Brooklyn at the center of the outbreak. One modeling study estimated that absent the vaccination campaign measles cases could have been 10 times greater.
In these instances and others from earlier decades, the outbreaks drove some people to voluntarily get vaccinated. But the disease also galvanized lawmakers to adopt policies to actively pressure individuals and parents to vaccinate themselves and their children.
The COVID pandemic shutdowns and vaccine requirements have provoked a backlash to such policies as coercive government overreach. Offit thinks public health authorities made mistakes in the pandemic: He disagreed with the decision to recommend subsequent COVID booster shots to all healthy young people. The result has been what he describes as a “libertarian left hook” against vaccine requirements.
The increasing partisan sorting around vaccines has made lawmakers in many Republican states wary of tightening restrictions in response to flagging immunization rates. Emboldened by the pandemic backlash and elevated by Kennedy, “medical freedom” activists have gained ground in efforts to expand shot exemptions or roll back school mandates altogether. Florida’s surgeon general, Dr. Joseph Ladapo, announced last September that the state aimed to remove all school and daycare vaccine mandates. “Every last one of them is wrong and drips with disdain and slavery,” Ladapo said at the time. For now, the plan has stalled in the state legislature.
West Virginia and Mississippi, two other Republican-dominated states, led the country in school immunization rates before the pandemic, but both now allow religious exemptions. The latter experienced a whooping cough outbreak last year, resulting in the state’s first death from the disease in more than a decade.
Since the pandemic, trust in public health authorities has eroded, but the current administration has only worsened that trend. HHS officials billed the unprecedented revision of the childhood schedule in January—a move temporarily paused by a recent court challenge—as a key step toward restoring trust. But Offit believes such changes made without data to support them only further undermine trust. He cited the CDC’s decision in 1999 to seek the removal of the preservative thimerosal from vaccines as a way to assuage concerns about a theoretical risk from ethylmercury exposure, even though data at the time did not suggest a safety issue. The move did not engender more trust, Offit argued, but provided fodder for anti-vaccine activists, who used the change to further amplify skepticism of vaccine safety.
While most of the public health community fears the resurgence of serious preventable diseases, some officials elevated by Kennedy don’t appear concerned about a change in immunization rates for disease like polio, which was declared eliminated in the U.S. in 1979 but has not been eradicated. Dr. Kirk Milhoan, the chair of the CDC’s vaccine advisory committee, suggested in January the decline in polio rates since the 1950s and ’60s could be a product of sanitation improvements more so than the vaccine—a common view among vaccine skeptics that has been widely refuted by polio researchers. Milhoan questioned whether the “risk” of taking the polio vaccine today is still worth it. “We need to not be afraid to consider that we are in a different time now than we were then,” he said.
Offit agreed things have changed, not about the disease or the importance of vaccination, but rather people’s trust in the public health system even in the face of real vaccine safety issues. When the first polio shot was released in 1955, one of the manufacturers, Cutter Laboratories, failed to render the virus inactive in a batch of more than 100,000 doses. As a result, 40,000 children contracted a mild form of the disease, more than 100 children and close contacts became permanently paralyzed, and at least 10 people died. The incident caused an uproar that sparked federal regulation and safety controls for vaccine manufacturing, but in the years that followed, it didn’t make much of a dent in the public uptake of polio vaccines.
“I don’t think there’s been a worse biological disaster in this country’s history, and that did not shake people’s trust,” Offit said. “It was just a different time.”
