Just one shot?

There are many different ways that people take care of themselves and their health. Hand hygiene, medication, doctors visits, and so much more. What about preventative medicine? In a society as interconnected as we are, a single illness has the capacity to claim countless lives and disrupt society as a whole. Over decades, even centuries, of research scientists have battled these diseases and viruses and given us the most critical tool to maintain our health: vaccines. Our health, and more specifically the health of our children, is at the forefront of nearly everyone's mind. With a discovery as ground-breaking and effective as vaccines, why are we seeing a decline in childhood vaccination rates coupled with an increase in cases of thought to be eradicated diseases? Vaccines are effective because of a series of immune events that “train” our body to recognize, attack, and fight off these viruses if they are ever naturally encountered. First, vaccines contain antigens. Antigens are a substance, such as a dead virus, which triggers an immune response via memory B-cells. This initial immune response triggers the start of antibody production. An antibody is the specific white blood cells that are produced from B-cells so that they can bind to antigens to signal to the rest of the immune system that it is foreign, or to directly target the antigen itself. Vaccines are a kickstart for the immune system to have been exposed to in a safe and controlled manner so that the slow, specific nature of the adaptive immune system has time to prepare for a possible infection. While this is the general guiding principle for vaccines, there are also a multitude of different types of vaccines based on the structure of the pathogen being defended against. For example, the MMR vaccine is a live vaccine, whereas the flu vaccine is a subunit vaccine. A live vaccine means that a weaker or inactive version of the pathogen is being used to initiate the immune responses previously discussed. In a subunit vaccine, only fragments of the pathogen are being used to initiate the immune response. There is not one single vaccine that will be effective against all pathogens, but scientists have tailored each individual vaccine to the specific pathogen so that the method of introduction to the immune system is the most effective strategy to properly equip the immune system for possible infection. 

Adaptive immunity. (2018). Khan Academy. https://www.khanacademy.org/test-prep/mcat/organ-systems/the-immune-system/a/adaptive-immunity

Centers for Disease Control and Prevention. (2024, August 10). Explaining How Vaccines Work. Vaccines & Immunizations; CDC. https://www.cdc.gov/vaccines/basics/explaining-how-vaccines-work.html

Pollard, A. J., & Bijker, E. M. (2020). A Guide to vaccinology: from Basic Principles to New Developments. Nature Reviews Immunology, 21(21), 1–18. https://doi.org/10.1038/s41577-020-00479-7