COVID-19 has changed the way we do pretty much everything: how we work, who we see, and the amount of hand sanitizer we use, to just name a few. Such extreme changes may challenge our sense of security and leave us all feeling a bit unsure in how to move forward. Now, with high profile rollouts of several COVID-19 vaccines, good news may be met with some hesitancy. Below we review what we know about these vaccines and how they may benefit not just you, but all of those around you as well.
What is a vaccine?
“a substance used to stimulate the production of antibodies and provide immunity against one or several diseases, prepared from the causative agent of a disease, its products, or a synthetic substitute, treated to act as an antigen without inducing the disease.” (Oxford English Dictionary definition)
In simple terms, a vaccine is a preventative treatment that trains the body to be better prepared to fight off a disease. The key to vaccines is building “immunity,” a term which is often misunderstood.
Immunity – what it means (and what people think it means)
“the ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells.” (Oxford English Dictionary definition)
The average person may think immunity means you cannot get sick from that disease. However, immunity simply means that your body is better able to fight off the disease. You are not “disease-proof” since you can still be exposed.
Where things get fuzzy:
This misunderstanding of immunity stems from “all-or-nothing” thinking – a way of reducing complex topics to simple, black or white outcomes. All-or-nothing thinking can impact several topics related to COVID-19, such as the status of one’s infection and the estimated risk of contracting illnesses. Examples of all-or-nothing thinking are, “If I’m not symptomatic, I don’t have COVID,” “If I’m not sick, I can’t get other people sick,” or even how we discuss the outcomes of COVID as either life or death (and ignoring the potential long-term cardiac, respiratory, and neurological effects ).
Recognizing “all-or-nothing” thinking is critical when considering the impact of available vaccines for COVID-19. There is a wide-spread assumption that when enough of the population has been vaccinated, we will achieve herd immunity, effectively halting disease spread. Additionally, the assumption is that mask wearing and the need for social distancing will become a thing of the past. But these assumptions are almost certainly wrong.
Becoming infected with a virus and not getting sick is not the same thing as not getting infected at all. Vaccines prime your body’s immune system to be better prepared, but it still must fight off the disease when you encounter it – and it is possible that you may still spread the virus to others. With a highly transmittable disease such as COVID-19, we each must do our part to reduce the potential disastrous impact this disease has on large populations (for a thorough examination of what infection and fatality rates would mean in real numbers, see C. Saper’s November 18, 2020 editorial in the Annals of Neurology )
What we know about COVID-19 vaccines
A global push for a COVID-19 vaccine has led to several exciting options in a relatively short amount of time. The speed of development may leave some uneasy, but these vaccines are just the latest innovation building upon half a century of research in coronaviruses (for an excellent overview of the COVID-19 vaccine development process, see P. Ball’s December Nature article ).
Preliminary results from the Phase III trials of the AstraZeneca/Oxford vaccine  were recently published in the journal Lancet. The good news is that this vaccine, like the ones from Pfizer and Moderna, appears to be highly effective – over 90% effective in protecting against severe symptomatic illness.
What does this mean?
If fully vaccinated (both does) and subsequently exposed to the COVID-19 virus, your chances of having severe complications, e.g., hospitalization and/or possible death, are much smaller than if you did not get vaccinated at all. Furthermore, serious side effects from the vaccine itself, like allergic reactions, are extremely rare; most people who do get side effects suffer minimal ones (e.g. a few days of achiness and fatigue). This appears to be true for ALL three of the vaccines [5,6].
Are people with epilepsy at higher risk of side-effects?
According to the Epilepsy Foundation, people with epilepsy are not considered high risk for side effects. If you have a history of having seizures after receiving a vaccine or have concerns, talk with your physician.
- The vaccine does not make you invincible, but it will help keep you from getting severely ill if you become infected.
- The known side effects from the available vaccines vastly outweigh the known consequences of a severe COVID infection.
A Note On Herd Immunity
Herd immunity is valuable and helps limit the spread of disease to vulnerable populations, but only if enough people’s immune systems are trained up to fight off day-to-day exposure of the disease. We know this from past outbreaks: this is why we aren’t having to cope with devastating waves of polio and smallpox infections every year.
Short version – get vaccinated: it can save lives.
About the Author
Jeremy Slater, M.D., has worked in the field of epilepsy for more than 27 years and currently serves as the Chief Medical Officer for Stratus. He served as the director of the Texas Comprehensive Epilepsy Program from 2004 through 2017, growing the center from a single neurologist and neurosurgeon to one of the largest epilepsy surgery programs in the country. Dr. Slater earned his medical degree at the University of Pittsburgh School of Medicine, in Pittsburgh, PA. He completed his residency in neurology followed by a fellowship in epilepsy and clinical neurophysiology at the University of Miami School of Medicine in Miami, FL.
 Mayo Clinic. COVID-19 (coronavirus): Long-term effects [Internet]. Rochester, MN: Mayo Foundation for Medical Education and Research; 2020 Nov 17 [cited 2020 Dec 22]. Available from: https://www.mayoclinic.org/coronavirus-long-term-effects/art-20490351
 Saper CB. What Are the Odds?. Ann Neurol. 2021;89(1):11-12. doi:10.1002/ana.25960
 Ball P. The lightning-fast quest for COVID vaccines – and what it means for other diseases [published online ahead of print, 2020 Dec 18]. Nature. 2020;10.1038/d41586-020-03626-1. doi:10.1038/d41586-020-03626-1
 Voysey M, Clemens SAC, Madhi SA, et al. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK [published online ahead of print, 2020 Dec 8]. Lancet. 2020;S0140-6736(20)32661-1. doi:10.1016/S0140-6736(20)32661-1
 Polack FP, Thomas SJ, Kitchin N, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine [published online ahead of print, 2020 Dec 10]. N Engl J Med. 2020;NEJMoa2034577. doi:10.1056/NEJMoa2034577
 Jackson LA, Anderson EJ, Rouphael NG, et al. An mRNA Vaccine against SARS-CoV-2 – Preliminary Report. N Engl J Med. 2020;383(20):1920-1931. doi:10.1056/NEJMoa2022483