A common claim, now again circulating, is that vaccines harm a person’s immune system, resulting in vaccinated people being less healthy than their unvaccinated peers.

Vaccines are like a practice test for your immune system. They teach your body how to fight germs without making you sick. When you get a vaccine, it shows your immune system a part of a germ or a weakened version of the germ. This doesn’t harm you, but it’s enough for your body to recognize it as an invader.

When a pathogen invades, especially for the first time, it can replicate in your body faster than your immune system can neutralize it. When that happens, you can get sick. Most pathogens will only cause minor illness, but some can cause serious illness, permanent damage, or even death. Luckily, we have developed vaccines against some of these more serious diseases.

The vaccination process introduces modified forms of pathogens to your immune system without causing disease, so if you encounter the actual pathogen at a later time, the memory B cells you developed from being vaccinated can recognize the antigens and quickly activate antibody production. Your body doesn’t know from one antigen to another, so your body doesn’t know that one antigen is from a pathogen or if it was from a vaccine. There is no difference in how your immune system responds to those antigens.

So, vaccines don’t destroy your immune function. They actually boost it by teaching your body how to recognize and fight off specific diseases. This way, if you’re ever exposed to the real thing, your body is ready to protect you, often without you even knowing it.

Now that measles is raging back to life in the UK (and probably soon across the U.S.), anti-vaxxers are claiming that MMR uptake rates do not matter since herd immunity against measles doesn’t exist. And that vaccinated kids are getting measles, proving that natural immunity is better.

The statement about measles vaccine coverage and herd immunity has several misleading or incorrect issues. Let’s break it down:

“The promise for herd immunity was a lie.”
Herd immunity is not a lie; it’s a well-established scientific principle. When enough people in a community are vaccinated against a disease, like measles, it can greatly reduce the likelihood of disease spreading in the community. This protects those who can’t be vaccinated, such as babies or people with certain medical conditions. The key is that a high enough percentage of the population needs to be vaccinated for herd immunity to work. For measles, this is usually around 95%.

“So now ‘vaccinated’ children are getting measles in epidemic numbers”
First, the vast majority of measles cases occur in unvaccinated individuals. While it’s true that no vaccine is 100% effective, the measles vaccine is very effective — about 97% effective after two doses. If community uptake rates dip below 95%, the risk for vaccinated and unvaccinated people increases. Let’s say 80% of children in a school of 200 students are vaccinated, and Unvaccinated Bobby brings measles back from his exotic vacation to the UK. We can be relatively certain that almost all of the 40 unvaccinated students will come down with measles. But, because the vaccine is only 97% effective, 5 vaccinated students could also become sick as the virus circulates through the student body. This isn’t an epidemic of the vaccinated. It’s math.

“Natural immunity has been decimated.”
This statement suggests that allowing a disease to run rampant through a community to create “natural immunity” is preferable to vaccinating them.  Before the measles vaccine, nearly everyone in the population got measles at some point in their life, although usually as children. Measles is so contagious that if 100 susceptible people were in a room with an active case, 90 of them would get measles. Today, very few people ever get measles because most people are vaccinated.

Relying on natural immunity means requiring virtually every child to get sick and 400-500 of them die every year.

Measles vaccination is a safe and effective way to prevent disease and protect public health. Herd immunity is critical to this protection, but it requires high vaccination rates to be effective. Vaccinated individuals are far less likely to contract measles than unvaccinated individuals, and the concept of natural immunity, while scientifically valid, comes with risks that can be avoided through vaccination.

A video of a “holistic pediatrician” from a public hearing at the Connecticut Capitol in 2020 claims that adjuvant boosters in vaccines cross the blood-brain barrier and cause many terrible health conditions.

Aluminum is the third most abundant element on earth and is present in many of the foods we eat, in much higher quantities than found in vaccines. Any aluminum injected from vaccines is metabolized in the body, and the vast majority of it is excreted within weeks

Is injecting aluminum different from ingesting it? Studies show us that the aluminum adjuvant is absorbed by the body so slowly that it raises the level of aluminum in the body negligibly.  But does it cross the blood-brain barrier, as suggested in the video?

Because the blood-brain barrier is actually quite good at keeping out those things it doesn’t need, such as proteins and viruses, we can be assured that aluminum adjuvants do not cross this barrier. This excellent video by Dr. Paul Offit explains the details about how the BBB works to protect us and our brains.

Even though we are reassured that aluminum adjuvants do not cross the BBB, there are some studies that show people with Alzheimer’s may accumulate more aluminum in their brains, the causation is less clear. It may be the degeneration makes the brain more susceptible to collecting aluminum. But one 2001 study suggests that vaccines may protect against developing Alzheimer’s.

How about neurodevelopmental differences or autoimmune issues?

Plenty of evidence tells us that vaccines do not cause autism. Not only do the studies done to date show vaccines are not in any way linked to autism, but studies indicate disorganization of the prefrontal cortex in the brains of autistic people. This finding links autism to development that takes place before birth. Of all the risk factors for developing autism, we know genetics looks the most likely and being vaccinated is not among them.

While molecular mimicry is a real phenomenon, its portrayal in the speech as a widespread issue caused by vaccines is misleading. The immune system is highly sophisticated and capable of distinguishing between self and non-self. This article looks at current research to conclude that vaccines with aluminum adjuvants do not cause autoimmune/autoinflammatory syndromes. The article looked specifically at the two vaccines–Hep B and HPV–mentioned in the video.