Why Vaccines Matter This School Year
By Danielle Frazee, MD
When I was in medical school, I signed up for a 10-mile trail race on the Superior Hiking Trail. It was a bold move—I wasn’t a runner, let alone a trail runner—and I had no real idea what I was getting myself into. I’d hiked a few trails before, but running up and down rocky terrain for hours was a completely different challenge.
In many ways, I think of that experience when I consider how our immune systems face the upcoming school year and flu season. Just like I was unprepared for the demands of the trail, our bodies can be unprepared for the barrage of viruses and bacteria we encounter each year. Without vaccines, our immune systems are left to tackle unfamiliar and potentially dangerous infections without a game plan or training—and that can lead to serious consequences.
After getting a taste of the rigor that is trail running (I tripped over several tree roots and turned around after a mile because my calves were sore), I decided I needed more training for my upcoming race. I wanted to feel confident going into race day that I was prepared for any obstacles that might come up. Muscle cramping? I learned to take salt tabs. Slippery declines? I learned to slow down and adjust my footing. Over time, I collected these strategies because I had first-hand experience with smaller, manageable challenges before the real test. That’s essentially how vaccines work. They give our bodies a preview of a pathogen (something that would make us sick) —just enough for our immune system to learn its patterns and develop a defense—without making us endure the full-blown illness. By the time the real “race day” arrives in the form of exposure to that virus or bacteria, our immune system is already trained and ready.
Some parents worry that children get “too many” vaccines, but the truth is that the number of antigens (parts of pathogens that stimulate the immune system) in today’s recommended vaccines is a tiny fraction of what kids encounter naturally. Just going to the grocery store, visiting a playground, or riding the bus exposes children to far more microbes than any vaccine schedule ever could. What vaccines provide is not random exposure, but safe, controlled training that prevents the devastating consequences of diseases like measles, whooping cough, and meningitis.
For school-age children, being up to date on vaccines is about more than just personal protection—it’s also about protecting classmates, teachers, and community members. This concept, known as herd immunity, means that when enough people are immune to a pathogen, it becomes much harder for diseases to spread. That’s especially important for those who can’t get certain vaccines for medical reasons or for those with weakened immune systems.
Heading into the school year, the stakes are especially high. Classrooms, cafeterias, and school buses are the perfect environments for germs to spread quickly. A single case of a highly contagious illness like measles can infect up to 90% of unvaccinated people who come into contact with it according to the CDC. Even illnesses that seem “old-fashioned” or rare are only rare because vaccines have kept them in check. History has shown that when vaccination rates drop, these diseases make a comeback.
Vaccination is not about eliminating all illness—just as my trail running training didn’t guarantee I wouldn’t stumble—but it greatly reduces the odds of severe outcomes. It turns potentially life-threatening infections into something our immune system can handle with confidence. School, like trail running, is full of challenges. But with the right preparation—whether it’s miles logged on a trail or immunity built through vaccines—we can face those challenges with resilience.
