In 2022, Florida weathered a bad outbreak of meningococcal disease, a type of fast-moving bacterial infection that can become fatal after entering the bloodstream or the lining of the brain and spinal cord. As the number of ill people climbed into the dozens, public-health officials scrambled to address clusters of cases, including one among college and university students. Campuses are primed for outbreaks: The bacteria spread through the kind of intimate or prolonged contact that’s rampant on campuses, where people are “kissing and sharing drinks, being in close quarters in dorm rooms and parties,” Sarah Nosal, the president-elect of the American Academy of Family Physicians, told me. College attendance is considered its own risk factor for infection, and many states—including Florida—require the meningococcal vaccine for students living on campus.
Soon, though, Florida’s policy may change. Earlier this month, the state’s surgeon general, Joseph Ladapo, announced his intention to end all vaccine mandates: “Every last one of them is wrong,” he said. Some vaccine rules—including the one applying to the meningococcal vaccine—are written into the state’s laws, but Ladapo has said his office will partner with Governor Ron DeSantis’s to push for necessary changes.
A canceled mandate alone may do little to change the risk of meningococcal outbreaks on Florida’s college campuses. The CDC still recommends these vaccines for preteens and teenagers, and currently almost all American kids in that age group get at least one dose. But Florida’s rebellion against vaccine mandates is part of a larger erosion of the immunization status quo, as childhood-vaccination rates in the United States decline, Robert F. Kennedy Jr.’s Department of Health and Human Services chips away at long-standing vaccine policy, and more families seek exemptions from state requirements.
These changes won’t affect only young children, who are supposed to get numerous shots in their first 15 months of life. If vaccination rates fall—due to changing federal recommendations, states eliminating mandates, increasing anti-vaccine sentiment, or some combination of all of the above—middle schools, high schools, and college campuses may also become particular breeding grounds for once-controlled illnesses.
Nosal’s youngest child is still in college, so the idea of outbreaks on campuses hits close to home: If her child got a preventable illness because she hadn’t been encouraged to vaccinate them against it, or because campus-vaccination rates were too low to squash transmission, she’d be devastated, she told me. (The AAFP in September broke with federal guidance by recommending COVID-19 shots for all children, adults, and pregnant people.)
Meningococcal disease (which includes meningitis) is a very real concern for teenagers and young adults in a less vaccinated world. “You can be fine one minute and dead four hours later,” Paul Offit, who directs the Vaccine Education Center at Children’s Hospital of Philadelphia, told me. Thanks in no small part to vaccination, meningococcal disease is rare in the United States. But it’s been on the rise since 2021—last year’s count of 503 confirmed and probable cases was the highest recorded since 2013—and the ages of 16 to 23 are a risky time for contracting these infections, relatively speaking. The CDC currently recommends that kids get their first meningococcal vaccine at age 11 or 12, then another when they’re 16; only about 60 percent of kids in the U.S. get both doses by the time they’re 17. Even fewer get a separate vaccine that targets a meningococcal subtype responsible for many cases among teens and young adults. (The CDC does not routinely recommend this shot for teens without special risk factors for infection, instead leaving the choice up to patients and their doctors.)
In recent years, the CDC’s Advisory Committee on Immunization Practices, the expert group that shapes the agency’s national vaccine recommendations, has considered dropping its recommendation for a first dose administered at age 11 or 12, since meningococcal infections are rare among preteens. Some experts have argued that axing that dose could set off a dangerous domino effect. Sarah Schaffer DeRoo, a primary-care pediatrician with Children’s National Hospital who has studied meningococcal disease and vaccination among college students, told me she worries that any disruption to established recommendations could cause confusion and contribute to further drops in vaccination rates, and more unvaccinated students means more chances for these infections to take root.
That consideration predated Kennedy—who recently dismissed all sitting members of ACIP and installed a variety of vaccine skeptics in their place—and the rejiggered committee may not implement it. (“Looking ahead, the new ACIP will continue to evaluate the latest gold-standard science before making future updates,” an HHS spokesperson said in a statement.) But Kennedy’s HHS has already shown willingness to reduce the number of immunizations children receive, such as by removing COVID-19 shots from the vaccine schedule for healthy kids.
If the committee continues to wind back vaccine recommendations, adolescents and teens could also be affected by vaccination decisions made on behalf of much younger people, Walter Orenstein, who formerly ran the United States Immunization Program, told me. Herd immunity only holds when protection is so high throughout an entire population that contagious illnesses are virtually unable to spread. If childhood-vaccination rates plummet, giving pathogens new targets in unprotected babies and young children, outbreaks won’t necessarily stay contained to those age groups. People of all ages—particularly those who are immunocompromised or under-vaccinated, but also some who are just plain unlucky—are bound to get sick too.
“If we stopped all vaccinations today, we won’t have huge outbreaks tomorrow,” Orenstein said. It would take time for the susceptible population to grow. But over time, largely forgotten illnesses could reestablish a foothold. If measles-mumps-rubella vaccination declined by 10 percent, for instance, the U.S. could see more than 11 million measles cases over the next 25 years, according to a 2025 modeling study. (Even at current vaccination rates, the disease may again become endemic and result in about 850,000 cases over the next 25 years, the study projected.)
Older kids and young adults would not be spared. Despite measles’ reputation as a childhood disease, about one-third of the cases recorded in the U.S. so far this year were among people 20 and older. And at least 8 percent of people sickened by measles this year had gotten one or more doses of the MMR vaccine—living proof that vaccinated people are also at risk when illnesses are given room to maneuver.
“This is what I call the new epidemiology of measles,” Michael Osterholm, who directs the University of Minnesota’s Center for Infectious Disease Research and Policy, told me. The fact that adults are already catching measles suggests outbreaks could easily emerge in high schools and on college campuses, particularly if vaccine coverage wanes—the last thing any school wants, given the disease’s extreme contagiousness.
Mumps is another concern, Offit added. It spreads best among people in close contact, such as students. Immunity can also wane over time, even among people who get vaccinated, which raises the chance of campus clusters. Across the board, if vaccination rates fall, “we’re going to be spending a lot more time dealing with outbreaks,” Osterholm predicted. “We’re going to have an increasing number of cases and, unfortunately, an increasing number of deaths among kids” of all ages.
To forgo vaccinations proven to prevent deadly and debilitating diseases is to accept the possibility of these grim outcomes—which parents haven’t had to think about for decades, as mass immunization has invisibly done its job. “That is the choice we’re making,” Nosal said. “We just don’t completely understand that choice because we haven’t seen it.” At least not yet.
