Abstract
From the time when the smallpox vaccine was successfully produced in 1798, vaccines have proven to be the most reliable means for preventing and controlling most infectious diseases because they significantly reduce morbidity and mortality associated with life-threatening infectious diseases. During the pre-COVID-19 era, the development, testing, and final approval for vaccines would take as long as thirty years and this was regarded as a normal procedure by most regulatory bodies. However, the devastating COVID-19 pandemic witnessed the development and approval of several vaccines in just six months from when the first SARS-CoV-2 case was reported in Wuhan, China. The speed and apparent ease with which the COVID-19 vaccines have been produced and approved has introduced a paradigm shift in the vaccinology field, creating an environment within which the production of vaccines for most infectious disease now seems possible. This chapter delves into the vaccine production and approval process and discusses the benefits of vaccines, the types of vaccines, and how they work. It also explores how lessons from the COVID-19 pandemic can contribute toward the expedited development, trial, and approval of vaccines against other devastating diseases of equally high, if not higher, mortality rates such as HIV/AIDS, TB, and malaria.