Something deeply unsettling is unfolding in America. A country that once led the world in championing the benefits of vaccines now has a Department of Health and Human Services that openly questions their safety. At the centre of this shift stands Health Secretary Robert F. Kennedy Jr., himself the founder of an anti-vaccine organization. There are growing fears that certain policy changes under his watch could prompt the handful of companies that manufacture childhood vaccines to simply stop selling them in the United States altogether. It is against this alarming backdrop that two Stanford University researchers have raised a once-unthinkable question: What happens if vaccines truly become unavailable?
Epidemiologist Mathew Kiang and infectious disease physician Nathan Lo built a sophisticated mathematical model focusing on four diseases that vaccines had effectively buried: polio, measles, rubella, and diphtheria. Running thousands of simulations for each disease, they calculated how many deaths and disability these illnesses could unleash across America over 25 years without vaccination. Their findings carry one unmistakable message — a future without vaccines is a future of catastrophe.
Take polio. The disease attacks the nervous system of young children and can cause permanent paralysis of the limbs or the muscles responsible for breathing. In the 1950s, countless patients were kept alive inside massive metal contraptions called iron lungs that forced air in and out of the body. Modern medicine has replaced those machines with ventilators, but it still cannot undo the paralysis itself. The researchers’ model estimates that without vaccines, an average of 23,000 people could be paralyzed by polio over 25 years — the equivalent of more than a thousand kindergarten classrooms full of children, frozen in their bodies for life.
The picture with measles is even grimmer. Measles ranks among the most contagious diseases in all of human history. An infected child can spread the virus before a single rash appears on their skin, and the virus itself can survive in the air of a room for up to two hours after the child has left. Before the vaccine arrived, between four hundred and five hundred Americans died from measles every single year. Over the last 25 years, only six people in the United States have died from the disease. But if the vaccine disappeared, the researchers’ model warns that measles could claim the lives of approximately 290,000 Americans within just 25 years — a number almost impossible to comprehend.
Rubella, commonly known as German measles, tends to be mild in children and adults. For an unborn baby, however, it is nothing short of devastating. If a pregnant woman is infected in the very early weeks of her pregnancy, there is up to a 90 percent chance her child will be born with congenital rubella syndrome — meaning heart defects, deafness, or blindness, and sometimes all three at once. Many of these children are also intellectually disabled, and roughly one in three does not survive their first year of life. A rubella epidemic in the mid-1960s left 20,000 newborns in America carrying this syndrome. If the vaccine vanished today, the effects would be slow to appear — the unvaccinated children would first need to grow into their childbearing years. But once that generation comes of age, the model shows cases would climb sharply, with as many as 41,000 babies potentially born with congenital rubella syndrome within 25 years.
Diphtheria was once known as the “strangling angel of children.” The disease’s toxin attacks the respiratory tract, causing dead tissue to build up in the throat like a thick sheet of leather, sealing off the airway. For those who survive suffocation, the toxin can go on to damage the nerves and the heart, and patients who appear to be recovering have been known to die suddenly weeks later. The only treatment is an antitoxin derived from horse blood, which is already in critically short supply around the world. Less contagious than measles or rubella but far more lethal, diphtheria kills one in every ten unvaccinated people it infects. Without the vaccine, this long-dormant strangling angel could quietly find its way back.
Researcher Kiang has noted that when his paper was first published, the most extreme scenario it described still felt largely hypothetical. A year later, his tone has changed. “Every week that goes by,” he said, “that seems more plausible.” His colleague Lo has said their goal was simply to show policymakers what certain decisions could set in motion. History proved that vaccines could reduce these diseases to footnotes in medical textbooks. This research is a stark and unsparing mirror, reflecting just how horrifying the future could become if the lessons of that history are forgotten.
