Editor's Note: Today's blog post is by Ellie Ohev Zion, health communications intern at The College of Physicians of Philadelphia. Ellie is a college student at Temple University, majoring in Public Health. She is interested in how Public Health information is spread and how communication helps the public understand information and create a healthier and safer environment.
Imagine a disease so contagious that almost everyone who meets someone with it gets sick. For decades, measles was like that — until vaccines changed everything. In 2000, health officials declared measles eliminated in the United States due to widespread vaccination, a moment public health experts celebrated as a major success. But today, measles is making a comeback, and the reasons may sound familiar to anyone who looks at vaccine history closely.
Right now, outbreaks of measles are increasing across the United States and other parts of the world because vaccination rates have dropped below the levels needed to stop its spread. In 2025, the U.S. experienced its worst measles year in over three decades, with more than 1,000 confirmed cases — the highest since the early 1990s — and experts are warning that the country could lose its status of measles elimination if transmission continues for 12 months straight. This matters because measles is extremely contagious, and even small declines in vaccination can create large outbreaks, as seen in multiple states and local school districts where vaccine coverage fell well below the 95% threshold needed for community protection.
One big reason for falling vaccination rates is vaccine hesitancy — when people delay or refuse vaccines despite their availability. Many parents today have concerns rooted in misinformation about vaccine safety. A common fear many have heard is that the measles vaccine, or the combined MMR vaccine, could cause autism, even though large scientific studies have found no association between vaccines and autism. This same fear has been amplified by online communities and social media echo chambers, where information that sounds scary spreads quickly, even if it isn’t true.
The strange thing is that the current fear surrounding measles vaccines isn’t new at all. Vaccine skepticism has existed almost as long as vaccines themselves. When Edward Jenner introduced the world’s first vaccine against smallpox in 1796, there was pushback from people who feared the new technology. By the mid-1800s, anti-vaccination groups had formed in England and the U.S., arguing against safety and individual rights. Fast forwarding to the 1960s, even after the measles vaccine was developed and licensed, some families were still slow to adopt it because they didn’t see the disease as a serious threat or trusted their own judgment over medical advice.
A turning point in modern vaccine fear came in 1998, when a flawed study suggested a link between the MMR vaccine and autism. That study was later discredited, and many subsequent scientific investigations have shown no link between the vaccine and autism. But the fear it sparked didn’t disappear quickly. People continued to worry about vaccine safety, and the idea stuck — shaping how many think about vaccines today. In a way, the hesitancy of parents in the late 1990s repeats debates from decades earlier: a mix of uncertainty, fear, and mistrust of expert voices.
When we look at how both past and present unfold, it’s clear that human reactions to vaccines — fear, doubt, concern, and hope — have a rhythm. We celebrate breakthroughs and scientific success, like the near-eradication of measles, but we also see waves of hesitation that slow those gains. Today’s measles outbreaks show how fragile public confidence can be when information spreads faster than understanding. Yet, the science behind vaccines has remained reliable, standing strong against misinformation when given a chance to be heard.
Understanding this history matters because it reminds us that current debates aren’t isolated events. They are part of a long story of people grappling with new knowledge, fear of the unknown, and the challenge of balancing personal choice with community health. By remembering where we’ve been — both the successes and the fears — we can better understand why today’s vaccine conversations feel familiar, and how we might help build trust in the science that protects us all.
Resources and Additional Reading
- Duke Health. (2024, March 5). Measles vaccine co-creator explains where fear came from — and why it is unfounded.
- Harvard Health Publishing. (2025, March 6). Measles is making a comeback — can we stop it? Harvard Medical School.
- History of Vaccines, College of Physicians of Philadelphia. (n.d.). Measles timeline.
- History of Vaccines, College of Physicians of Philadelphia. (2023, October 19). Top ten anti-vaccine myths — debunked again.
- World Health Organization. (n.d.). History of measles vaccination.