the official magazine of the brain injury association of california

Debates about vaccination go back as
far as 1796 when the world’s first accination
was performed. Now, COVID-19 vaccines have
renewed the conversation with a focus
on neurological complications.

COVID-19 has been a presence in all of our lives for more than two years — and for many, so has the vaccination debate. Since the U.S. Food and Drug Administration (FDA) authorized the first COVID-19 vaccine, more than one hundred million people in the U.S. have been vaccinated. While the mainstream medical community has promoted COVID-19 vaccination — with high profile organizations like Johns Hopkins Medicine among others expressing their views that all authorized COVID-19 vaccines are highly effective at preventing serious disease, hospitalization and death from COVID-19 — there are still many who question not only the safety of COVID vaccines, but the safety of vaccines in general. A SHORT HISTORY OF VACCINES The first vaccines were based on using weaker strains of viruses to generate immunity, while not giving the recipient of the vaccine the full-blown illness or, preferably, any symptoms of the disease at all. In May 1796, a British physician named Edward Jenner tested his hypothesis that direct inoculation of a person cowpox, which is not deadly, would render that person immune to smallpox, which was. Jenner based this theory on his observations of milkmaids. Those milkmaids who had acquired cowpox through their contact with cows were immune to smallpox even when exposed multiple times to the deadly disease. Jenner’s detailed descriptions of his experiments convinced his colleagues and the authorities that inoculation with cowpox — which he called vaccination —

was a viable way to protect people from smallpox. Another important figure in the history of vaccination was Louis Pasteur. Pasteur stepped onto the world stage with a famous experiment borne out of necessity. In July 1885, a rabid dog attacked a boy named Joseph Meister. At a time when this would have been a death sentence from rabies, Joseph’s mother asked for help from Louis Pasteur, who she heard was working on a cure for rabies. Pasteur inoculated the child with 13 increasingly strong doses of an experimental rabies vaccine. At the end of the treatment, the child did not develop rabies, and a new era of vaccination began. EARLY ANTI-VACCINATIONISM The beginnings of anti-vaccinationism were rooted in the idea of personal rights rather than health risks. In the early nineteenth century, smallpox vaccination in Europe became mandatory and societies of anti-vaccinationists formed to protest what they saw as infringement of individual liberty. Anti-vaccinationism spread to the United States later that same century, largely by visitors and immigrants from Europe, and it has been with us ever since. GENERAL VACCINE CONCERNS Vaccines, though designed to protect from disease, have been shown to cause side effects that range from mild-to-serious. According to the Centers for Disease Control and Prevention (CDC), the most common side effects of vaccination are soreness, swelling or redness at the injection site. Some vaccines

are associated with fever, rash and achiness. Serious side effects from vaccination appear to be rare, but may include lifethreatening allergic reaction, seizure and even death. However, according to the CDC, when considered on a population basis, the incidence of serious complications of vaccination is minute when compared with the outcome of natural infection. In order to understand the range of possible vaccination side effects, it is useful to compare a vaccine with relatively few associated side effects, such as the Haemophilus influenza type B vaccine, with a vaccine known to have many potential side effects, such as the smallpox vaccine, which is still used in a military context today. In the case of Haemophilus influenza type B, side effects may include redness, warmth or swelling at the injection site and elevated fever with no serious side effects having been reported. In contrast, with the smallpox vaccine, risks include encephalitis (inflammation of the brain which can lead to permanent brain damage), severe infection beginning at the vaccination site and even death — for every million people vaccinated for smallpox, up to 52 people could experience life threatening side effects. THE CASE FOR VACCINATION Even with anti-vaccine sentiment and vaccine concerns, the origins of vaccines do seem to make a great case for themselves, and modern science backs this up. According to the National

Foundation for Infectious Diseases, The US has a robust approval process to ensure that all licensed vaccines are safe. They say that potential side effects associated with vaccines are uncommon and much less severe than the diseases they prevent. According to the CDC, getting all recommended vaccinations is a powerful step in taking charge of your health. They say that when given as directed, FDA-authorized vaccines can prevent severe disease and save lives. WHEN HARM IS CAUSED BY VACCINES When vaccines first began to be widely used, people who experienced serious side effects from vaccination had little recourse to compensation from manufacturers, physicians or the government. This was particularly a problem when vaccine production techniques were in their infancy, and contamination of vaccines occasionally occurred during or after manufacture. Since the passage in 1902 of the U.S. Biologics Control Act, which initiated the regulation of vaccines, such problems with negligence in manufacturing have greatly declined. As product liability law evolved during the 20th century, it eventually provided an avenue for compensation for individuals harmed by vaccines — they could sue vaccine manufacturers or they could sue physicians who administered vaccines. To help keep track of adverse reactions to vaccinations, the CDC and the FDA established The Vaccine Adverse Event

Reporting System (VAERS) in 1990. According to the CDC, VAERS is used “to detect possible signals of adverse events associated with vaccines.” About 30,000 events are reported each year to VAERS. Between 10% and 15% of these reports describe serious medical events that lead to hospitalization, lifethreatening illness, disability or death. COVID VACCINES According to the National Foundation for Infectious Diseases, as of April 15, 2022, 19 vaccines have been authorized for emergency use and 12 given full approval for use. In 2020, the FDA authorized two mRNA COVID vaccines for emergency use. In 2021, the FDA approved the Pfizer-BioNTech COVID-19 vaccine for people ages 16 and older, and following that, the Pfizer-BioNTech vaccine for children ages 5 through 15. In 2022, the FDA approved the Moderna COVID-19 vaccine, now called Spikevax, for people age 18 and older. Researchers continue to study and develop several other COVID-19 vaccines. It’s estimated that COVID-19 vaccination results in a low risk of another infection with a similar variant for at least six months. HOW COVID VACCINES WORK According to the CDC, COVID-19 vaccines work with your immune system so your body will be ready to fight the coronavirus if you are exposed to it — including coronavirus variants. In addition, COVID-19 vaccination might offer more protection than becoming infected with COVID-19. A recent study has shown that unvaccinated people who already had COVID-19 are more than twice as likely as fully vaccinated people to be reinfected with COVID-19. Recent research also suggests that people who got COVID-19 in 2020 and then received mRNA vaccines produce very high levels of antibodies that are likely effective against current and possibly future variants. Some scientists call this hybrid immunity however further research is needed to confirm this phenomenon. DO COVID VACCINES EFFECT THE BRAIN? Though cases of neurologic symptoms related to COVID vaccination are uncommon, they are not unheard of. Two cases, published in the Cureus Journal of Medical Science, show that neurological inflammatory responses and the presence of neurooncologic lesions are possible after COVID vaccination. The journal describes two patients that presented with neurologic deficits that were not present prior to being vaccinated. One of the cases presented in the article was of a 58-year-old woman who experienced high-grade fevers, slurred speech and facial droop approximately two weeks following her second dose of a COVID-19 vaccine. According to the journal, the patient’s symptoms were attributed to post-vaccination Bell’s Palsy. Her fevers resolved over the next 24-48 hours as is typical with post-vaccination symptoms, however facial weakness persisted until approximately two weeks later when she developed acute

worsening of her facial droop with associated slurred speech, drooling as well as left arm and leg weakness. A contrastenhanced MRI of the brain demonstrated a large hematoma in the right frontal lobe. The patient underwent surgery to remove the hematoma. The second case presented in the journal was of a 52-yearold woman who developed severe headache and neck stiffness associated with intermittent high-grade fevers four days after her first dose of a COVID-19 vaccine. Contrast-enhanced MRI scans showed an abnormal mass on her brain. RISK VS. REWARD Despite this evidence of COVID vaccines effecting the brain, studies have shown that adverse events after COVID vaccination are rare and many COVID vaccines have proven over 90% effective with no safety threat. Additionally, other studies have shown that brain health may be more at risk after COVID infection than after vaccination. Whether or not to receive a COVID-19 vaccination is a personal decision, however, it is important to be aware of the potential adverse effects.