A Short History of Vaccines and the Rapid Development, Mechanism and Efficacy of the COVID-19 Vaccine

Abstract

The first significant breakthrough in the use of vaccines to protect against infection was the development of the smallpox vaccine in 1796. Since then, there has been tremendous progress in scientific research and discovery that has led to the current arsenal of highly-effective vaccines that exist today. A vaccine is meant to train the body's immune system into remembering a specific bacteria or virus so as to be able to robustly battle against it. The immune system develops an immune memory, which is then used to rapidly respond to the pathogen and prevent it from causing disease.1 Most traditional vaccines were originally based on a weakened or inactive form of a virus. The rise of the COVID-19 vaccine occurred in record time, gaining emergency use authorization (EUA) in just under a year. The power of mRNA-based vaccines was highlighted particularly through the widespread use of the Pfizer and Moderna COVID vaccines. While the mRNA-based vaccines are preferred, several other vaccines were developed through classical methods to protect against COVID. The variety of vaccines, while all effective, vary in their efficacy rates and protocols. There are specific side effects and risks that pertain to each vaccine. Even with multiple successful rounds of clinical trials and testing of the COVID vaccine, there is still a significant subset of the population who is against vaccination for personal, political or religious reasons. The rise of new variants of the virus and breakthrough cases among the already vaccinated present additional challenges that will drive future research in the field and fuel the race to come up with a pan-coronavirus vaccine.