A Short History of Measles and Vaccine Hesitancy

The graphs accompanying this article show that vaccination rates have risen over the last ten years in California, while declining in most of the rest of the country. The California increase in vax rates correlates with the aftermath of the 2014 Disneyland Measles Outbreak, which caused over 300 measles infections, mostly in Southern California and Canada, and overwhelmingly among unvaccinated individuals. It also sparked debate on vaccine hesitancy and led to California Senate Bill 277, which revoked the “personal belief” exemption, thus tightening the rules around vaccination requirements for K12 public school children by eliminating nonmedical exemptions.

SB 277 was co-authored by Senators Richard Pan (who was a physician) and Ben Allen. At the time, some California public schools had vaccination rates below 60%, even though a 95% rate is required for Community Immunity (herd immunity) for many diseases, including measles. Though the bill was supported by the California Medical Association, the American Academy of Pediatrics, the PTA and California Children’s Hospital Association, there was loud and aggressive opposition by a tiny number of anti-vax activists, who tried (but failed) to get Pan recalled. They also called him a Nazi and made death threats against both him and Allen.

It takes a serious level of fear and anger to want to kill someone. So, what was driving this fear and anger?

A major factor is the false belief that vaccines cause autism. For new parents, autism can be a terrifying diagnosis. So, if there is any evidence that something specifically is causing autism, it makes perfect sense to try and avoid it. And if parents believed that the state was imposing an autism-causing drug on their children, it is not hard to see why they’d associate the law-makers with Nazis, and the drug with Zyklon B. To a rational, educated person who understands that the risks associated with vaccines are actually miniscule compared with the risks associated with the diseases they protect against, this kind of thinking by anti-vaxxers probably seems absurd, or ignorant. However, it’s not just an issue of education versus ignorance. Consider that Marin County, California, one of the nation’s most affluent and highly educated communities, once had one of the lowest vaccination rates in the state.

One reason people have associated vaccines with autism stems from the common mistake of conflating causation with correlation. Autism is often diagnosed in children around the age of two, which is around the same age that many childhood vaccinations are given. Many parents of autistic children got their diagnoses within a year or so of their children’s vaccinations and they made the assumption that the two were connected when, in actuality, it was a coincidence. Dozens of peer-reviewed studies have confirmed that there is no increased risk of autism due to vaccinations.

The belief that vaccines caused autism really took off in the late 1990s. After British physician Andrew Wakefield published his fraudulent 1998 Lancet article, falsely showing a link between the MMR (Measle, Mumps, Rubella) vaccine and autism, there was a sharp decline in vaccination uptake. However, other researchers were unable to replicate Wakefield’s results (something that should be easy to do if the study was valid). Additionally, journalist Brian Deer discovered that Wakefield had a significant conflict of interest because he stood to earn up to $43 million per year selling test kits. And the British General Medical Council (GMC) later found that Wakefield was guilty of mistreating developmentally delayed children.

When Wakefield’s study was discovered to be fraudulent, Lancet retracted his paper and the GMC revoked his medical license. In 2004, he moved to the U.S., where he continued to push his bogus anti-vaccination claims, directing the pseudoscience propaganda film “Vaxed.” Robert De Niro, whose son is on the autism spectrum, removed the film from the Tribeca Film Festival. However, proponents of the vaccines-cause-autism hypothesis, including U.S. Health & Human Services boss Robert F. Kennedy Jr., continue to push this lie. For a while, they tried to blame thimerosal, a mercury-containing preservative that was used in vaccines since the 1930s. However, in 1999, thimerosal was pulled from vaccines as a precautionary measure. And, guess what: autism rates continued to climb anyway.

Today’s measles outbreak is currently close to 300 cases, primarily in Texas and New Mexico, but with cases spreading to Oklahoma and other states. And nearly every one of those cases is in an unvaccinated patient. There have also been two deaths, one in Texas and one in New Mexico. However, in the U.S., measles mortality is general around 1-2 deaths per 1,000 cases. Because measles, unlike Covid and Influenza, does not mutate rapidly, this is unlikely due to the evolution of a more virulent strain. Rather, the nearly 300 documented cases today are likely a gross undercount. The actual number may be closer to 500 or even 1,000. And we may not even be at the peak yet, particularly considering how low the vaccination rates currently are.

Back in 2015, when the California’s vaccination rates were lower, and its legislature was considering SB 277, one of the public faces of the debate was a 6-year-old Marin County boy with leukemia, named Rhett Krawitt. His parents argued that it was not safe for him to attend school with unvaccinated children, since he was immune-compromised and at increased risk of contracting a deadly disease from them. At the time, 20% of Marin’s students had opted out of the required vaccinations. Rhett, himself, spoke to the school board, as well as the state legislature, contributing to Marin County’s shift from being one of the lowest vaccinated counties in California, to one of the highest.

With the 2nd measles death of the year, and all the misinformation coming from America’s fake health and science boss RFK Jr., as well as the continued proliferation of anti-vaccine lies and hysteria, how about a close hard look at the facts:

1. CLAIM: RFK Jr. said that measles outbreaks are not unusual in the U.S.
FACT: The MMR vaccine is so effective that measles had been eradicated in the U.S. by the early 2000s. So, NO, measles outbreaks were NOT usual. In fact, they were nonexistent, at least until recently, when vaccine hesitancy started to grow due to the lies and disinformation coming from people like RFK Jr.

2. CLAIM: Measles is not serious.
FACT: In the U.S., the mortality rate for measles is around 0.1-0.3%. (https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00164-1/fulltext). A gambler might consider this to be low odds of dying from the disease. However, just a few years ago, one’s chance of dying from the disease was ZERO because the disease didn’t exist in the U.S. The two people who died of measles over the past few weeks would not have died if vaccination rates were still at 95% or higher.

3. CLAIM: Measles is not serious.
4. FACT: In lower income countries, the mortality rate for measles is around 3-4%, which is quite high. This is due primarily to the effects of malnutrition, which weakens the immune system. Trump’s slashing of USAID funding will likely result in an increase in measles deaths in countries that once relied on USAID to support their vaccination programs.

5. CLAIM: Measles is not serious.
6. FACT: 20% of unvaccinated people who catch measles in the U.S. will become hospitalized due to complications; 5% of children who get measles will develop pneumonia from the disease; 0.1% of children who get measles will develop encephalitis; and unvaccinated pregnant women who catch the disease have an elevated risk of having premature births or babies with low birth weight. (https://www.cdc.gov/measles/signs-symptoms/index.html). Measles also impairs one’s immune system, making them more susceptible to other infections, and it can cause brain swelling, seizures, blindness, deafness, and brain damage.

7. CLAIM: Measles is not serious.
8. FACT: 7-10 years AFTER a measles infection, survivors still run the risk of developing Subacute Sclerosing Panencephalitis (SSPE) a rare, but fatal disease of the central nervous system. From 1989-1991, they estimate that 7 to 11 out of every 100,000 people with measles were at risk for developing SSPE. That risk is higher for those who contract measles before the age of 2. (https://www.cdc.gov/measles/signs-symptoms/index.html) And, of course, that risk is 0 for communities with a 95% or higher vaccination rate.

9. CLAIM: MMR vaccine is more dangerous than measles. OR it causes febrile seizures in kids.
FACT: Febrile seizures are extremely rare with vaccines, including MMR. 0.03-0.04% of kids who get the MMR vaccine will get febrile seizures, and most will recover fine. But the risk of febrile seizures is much higher if you actually get measles. (https://www.cdc.gov/vaccine-safety/vaccines/mmr.html). Therefore, the vaccine is actually protective against this symptom.

10. CLAIM: The measles vaccine is not very effective
FACT: It is 97% effective, one of the highest rates for any vaccine out there. What this means, in actuality, is that 97% of those who receive the vaccine will develop lifelong immunity, and will have almost no risk of ever catching measles, spreading it to others, or dying from it. The 3% for whom it does not provide full lifetime immunity are still protected from ever catching the disease, assuming the community vaccination rate is at 95% or higher.

11. CLAIM: So, what if I’m not vaccinated? The disease is rare. I’m not going to catch it.
12. FACT: Measles is the most infectious disease known. 90% of unvaccinated people who are exposed will get measles. (https://www.nfid.org/resource/frequently-asked-questions-about-measles/) I guess if you always wore a properly fitted N95 in public you might be safe-ish. But how many anti-vaxxers out there actually wear masks?