The moment a public health initiative is just too fantastic.
Imaged: A life-saving device. Unsplash user Ed Us shot this photo.
It is unusual to have to persuade someone over 60 of the benefits of immunizations. There are few outliers, but generally speaking, folks from my dad's generation would respond with a resounding "Hell, yes!" when asked whether they believe immunizations are beneficial. People in their social circle have interesting anecdotes to share, such as the child in their class who became crippled from polio, the neighbor whose baby died from whooping cough, or a friend who had trouble conceiving due to a childhood episode of mumps.
However, these illnesses have almost vanished in the decades after the development of immunizations for children. It is well-known that the United States eradicated measles in the year 2000. Measles has not been "eradicated," although there have been no recent cases in the nation. This does not imply that the illness has vanished entirely.
Prior to the advent of the measles vaccine, the illness had a relatively well-understood course. It’s a classic example of disease modeling that we still use today since measles outbreaks in an unprotected community are highly predictable. In most communities, measles has a 2-year cycle where it infects most of the susceptible children in the first year, then you enjoy a year of low measles rates as additional kids are born, then the cycle begins again.
Obviously, the vaccination altered all of that. The United States used to see upwards of 400,000 cases of measles a year in the early 60s. The vaccine was approved in 1963 and began being administered frequently throughout the nation shortly after. By 1970, the rates had plummeted by more than a factor of 10, and measles was essentially a thing of the past.
Measles cases in the US, by year. Source: CDC. The figures from the 1971 AJPH article are also quite vivid, indicating how sudden the reduction was.
Most parents these days have basically no understanding what measles is. It’s simply an old person thing, like how women had their husband’s consent to obtain a credit card until the 1970s. Parents in 2024 have never heard of a child being permanently disabled or dying after a case of measles because it’s so very rare these days. This disconnect from the reality of infectious disease makes many of the myths about measles—like the bizarre idea that it’s not a dangerous disease if you’ve got a good diet—much more understandable.
None of the diseases we vaccinate against are innocuous. Measles causes very nasty pneumonia in some children. There’s also a rare complication from measles called subacute sclerosing panencephalitis (SSPE), where the virus infects people’s spinal cords and brains, usually resulting in death. As this 2010 case study of a 22 year old woman from Australia shows, it can happen to otherwise healthy people who have no known risk factors. It’s hard to know precisely how many people get SSPE, but the number is estimated to be around 1 in 10,000 for older kids and 1 in 5,000 if the infection happens before they turn 5. SSPE is extremely dangerous, with a fatality rate north of 90%.
It’s easy to discount rubella—German measles—if you’ve never known someone who had it during pregnancy. Tetanus is an awful disease that almost no one dies of in the US anymore because of the vaccine. It’s very hard to be appropriately worried about problems that you’ve never experienced or even heard of outside of history books.
The problem is that vaccines have become a victim of their own success. People who’ve experienced vaccine-preventable diseases understand the cost/benefit equation. There’s even some evidence of this happening, with pre-COVID studies showing somewhat lower vaccine hesitancy in older parents than younger ones. It wasn’t a hard and fast rule, but generally people who knew someone who died of diphtheria understand why the DTaP is such an important immunization.
People who’ve never experienced that experience just don’t know what they don’t know.
With all this, it’s not hard to see how we got into a place where the current US administration is openly anti-vaccine. Yes, it’s partially a blowback against COVID-19, but it’s also, in my opinion, at least partly because people have become divorced from the reality of what infectious diseases can do. People have no understanding what a huge measles outbreak looks like, so the concept that vaccinations are hazardous is much simpler to accept than it was in the 1980s.
Given the current US administration’s antipathy towards vaccinations—with one of the world’s most virulent anti-vaccine advocates poised to become secretary of the Department of Health and Human Services—it's quite likely that these preventable diseases will see a resurgence. The parents who have become more worried about vaccine side effects will once again watch as disease takes years off their children’s lives, and the mood will probably start to shift.
I doubt that the anti-vaccine sentiment will last long in the face of real disease outbreaks. We know how this works because we’ve seen it before. In 2018, two children died due to incorrectly prepared measles vaccines in Samoa. This led to a sharp drop in vaccination rates across the country, in part driven by overseas anti-vaccine rhetoric, including an appearance by RFK Jr himself. Predictably, after the vaccination rates fell to 34%, there was a massive outbreak in 2019. In a few short months, around 1 in 5 Samoan kids had contracted measles, and dozens had died. The eventual death rate for all infants in the small Pacific island country was nearly 1%. Faced with such tragedy, the government took swift action, and by December 2019 vaccination rates were once again well above 90% in Samoa.
It’s unlikely that death rates would be that high in the US. While some consequences of measles happen even in otherwise healthy kids, a big risk factor for severe pneumonia is vitamin A deficiency, which is relatively uncommon in high-income countries.
That being said, measles still causes a great deal of ill health and death even in high-income regions. A death rate 10x lower than the Samoan one would still kill thousands of children if there was a major outbreak in the US.
Which brings us back to the problem with vaccines. They are too effective. If no one ever sees the damage that infectious diseases can do, then many people assume they are harm-free. This makes the potential harms of vaccines seem much more problematic than they really are.
I suspect this attitude will be short-lived. If the current US administration gets their wish, and immunization rates plummet across the country, it will fast become obvious why we choose to vaccinate our children. It’s impossible to sustain anti-vaccine myths about mercury and autism in the face of PICUs packed with really sick kids.
Anti-vaccine attitude seldom lasts beyond the first significant outbreak of illness. This wouldn’t be a problem, but the cost is measured in children’s lives.