Do vaccines cause brain damage? No, there's no evidence that's true: Although vaccines are not risk-free, there is an almost universal consensus in the medical community that they are safe and save millions of lives each year. A person is far more likely to be harmed by a serious complication, such as brain damage, from a disease than by a vaccine.
The claim appeared in a Facebook post (archived here) on December 21, 2021. It includes video from an interview between well-known conspiracy theorist Alex Jones and Dr. Russell Blaylock. Around the 12:40 mark, Blaylock said:
There is a very firm, well-demonstrated scientific method by which these vaccines are causing brain damage, prolonged brain inflammation and excitotoxicity in the brain that goes on for decades, possibly a lifetime, that has the potential of increasing a number of neurodegenerative diseases, like Alzheimer's, Parkinson's, ALS [amyotrophic lateral sclerosis].
This is what the post looked like on Facebook at the time of writing:
(Source: Facebook screenshot taken on Wed Dec 23 16:42:07 2021 UTC)
Shortly after the 16-minute mark, Blaylock added:
Millions of people are having their lives destroyed, and their health destroyed, by this crazy vaccine policy. I mean, we're not even reasonable now.
He and Jones were not talking about specific vaccines, just vaccines in general. And the opposite of what Blaylock said is true.
According to the World Health Organization, vaccines are believed to save 2 million to 3 million lives each year. Vaccines are not risk-free, but a person is far more likely to be harmed by a disease than by a vaccine.
Blaylock was repeating a somewhat common myth that attempts to tie vaccines to neurological disorders. The belief was explored in a 2015 paper in the Journal of Preventative Medicine and Hygiene titled "The 'urban myth' of the association between neurological disorders and vaccinations," which mentions Blaylock. The paper notes that just because a neurological disease arises after the administration of a vaccine, it doesn't mean that disease was caused by the vaccine. It reads:
In reality, it should be borne in mind that the case reports published in the literature have almost always shown only a temporal association between vaccination and neurological events, while controlled studies have either excluded such associations, as in the case of the MMR vaccine and autism, or have been unable to establish a causal link between the vaccine and severe neurological reactions, such as in the case of diphtheria, tetanus and pertussis vaccines and optic neuritis.
The paper continues:
In conclusion, we can say, with little risk of error, that the association between modern vaccinations and serious neurological disorders is a true 'urban myth'.
Blaylock and Jones also discussed the issue of vaccines during pregnancy. At the 21:30 mark, Jones claimed:
Vaccinating pregnant women is a death sentence in many cases.
There's no evidence that's true.
It is true that some vaccines are not recommended during pregnancy -- such as the shots for HPV, chicken pox, and the measles, mumps and rubella (MMR) vaccine -- but a number of other vaccines -- like the Tdap vaccine and the inactivated flu vaccine -- are safe and recommended, according to the Centers for Disease Control and Prevention. Vaccines help to protect the mother, as well as their babies from serious diseases early in life.