On Nov. 10, 2025, the Pan American Health Organization (PAHO) revoked Canada’s measles elimination status. More than 5,000 cases have been reported since the outbreak began in October 2024. After a quarter century of controlling measles spread, Canada failed. The U.S. will likely soon join its northern neighbor in this ignominious designation, thanks to the resurgence of the anti-vaccination movement, which has been given new clout with Robert F. Kennedy Jr. at the helm of the Department of Health and Human Services (HHS).
Measles is the most highly-contagious disease known to science. If 10 unvaccinated people are in a room with an active case, nine will go on to become infected. In 2025, 12% of the 1,700 plus U.S. measles cases were hospitalized, with the highest rate, 22%, among children younger than 5 years old. Three people have died in the U.S. and two in Canada. Complications include pneumonia, encephalitis, deafness, and rarely, a fatal neurological disorder, subacute sclerosing panencephalitis (SSPE). Measles also has an insidious capability to cause “immune amnesia“, whereby immune responses to other pathogens are erased by the virus, leaving an individual susceptible to conditions they once had immunity to.
Elizabeth Jacobs is an epidemiologist and professor emerita at the University of Arizona and a founding member of the advocacy group Defend Public Health.
James Alwine is a virologist, a professor emeritus at the University of Pennsylvania, a visiting professor at the University of Arizona and a fellow of the American Academy for Microbiology and of the American Association for the Advancement of Science, and a member of the coordinating committee for Defend Public Health.
This was made worse when Senate Republicans confirmed Kennedy as Secretary of HHS, despite the objections of tens of thousands of scientists, healthcare providers, and public health practitioners. Kennedy is an avowed anti-vaccination proponent who chaired Children’s Health Defense, an organization that regularly promotes vaccine misinformation. He is also a conspiracy theorist and has claimed that COVID-19 is a “bioweapon” engineered to “attack Caucasians and Black people” while sparing Ashkenazi Jews; that WiFi causes brain cancer; and that drug use, not HIV, causes AIDS. His appointment opened the door to install anti-vaccine proponents as leaders in public health, such as replacing the members of the Advisory Committee on Immunization Practices with several individuals with links to the anti-vaccine movement. In confirming Kennedy, Senate Republicans utterly failed the people of the U.S. and demonstrated a cavalier disregard for decades of scientific achievement.
Over the past two decades, Kennedy has heavily influenced the anti-vaccine movement. Now as HHS Secretary, his position of power is furthering his influence. By encouraging doubt in science and medicine, many parents become confused and afraid to vaccinate their children, while others develop passionate distrust and join his movement. This distrust can then be used to justify irrational and harmful actions, such as cutting funding for mRNA vaccine research. And the ripple effects of Kennedy’s actions are empowering anti-vaccine movements around the globe. It is why Canada and the U.S.are currently experiencing the highest number of measles cases in over two decades.
Kennedy must be removed from office
What’s more, an undervaccinated population undermines national security; a 2023 Department of Defense report specifically identified COVID-19 vaccine misinformation as a threat to military readiness because it undermines disease prevention and the acceptance and adherence to mitigation policies. The report further highlighted the importance of a robust government vaccination research program in order to avoid preventable disease outbreaks, which undermine national security.
As the anti-vaccine movement continues to be nurtured by Kennedy and his followers, this threat will only continue to expand and grow more severe. Removing state vaccine requirements for school entry — as has happened in Florida — is demonstrative of this, and represents an unacceptable risk.
Given these dangers, what can be done to stem the anti-vaccine movement and the dangers it carries with it? Most importantly, as we wrote in our report for the public health advocacy group Defend Public Health, Kennedy must be removed from office. There can be no improvements in public health or vaccination rates as long as he continues his destructive reign.
Social media and legacy media companies need to take meaningful and effective steps to end the catastrophic spread of misinformation on their platforms. But they have no real motivation for doing so, since sensationalistic, fact-free health claims are major drivers of engagement, and therefore, of profit.
As Gregg Gonsalves pointed out in his recent piece in The Nation, we must fight these efforts by building a massive movement to support and defend public health. It is time for concerned individuals to pitch in by monitoring state-level attempts to undermine vaccines and taking action to stop them. Finally, the people of the United States need to elect representatives who are better stewards of the health of our people, our communities, our nation, and ultimately, the entire world. The recent elections in November 2025 suggest that Americans are already enacting change at the ballot box. Public pressure can help push public health to the forefront.
Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.
