Vaccines and vaccine resistance: Past, present and future

ABSTRACT

Background: Edward Jenner, by any definition would be considered the father of vaccinology. His use of cow pox virus for vaccinating against small pox is the prime example of a live vaccine. Using a virus that has very low virulence for humans and therefore, fits the definition of attenuated. Hesitancy towards a vaccine of this type, much before the science of microbiology and immunology were established, would have been justifiable. In the first half of 20th century, large number of vaccines became available for childhood diseases with significant morbidity and mortality. Around the same time global travel and trade led to escalation in the widespread transmission of diseases caused by microbes. Objective: The objective of this narrative is to offer a balanced view of science behind vaccines, their current status and advances expected in the near future. At the same time the various types of reactions from public at large towards vaccines over past decades are reviewed. Content This narrative provides a historical perspective of vaccine development, reviews mechanisms of vaccine induced protection, currently available vaccine technologies and vaccines. The focus is on newer vaccines including those utilizing viral vectors and gene based vaccines. Based on the times during which this narrative is being written, messenger RNA vaccines are discussed in detail. Conclusion: The content and review of literature offered in this review makes the impact of vaccines on human life clear. It is also to be accepted that resistance and hesitation towards vaccines is nothing new or limited to vaccines being used during the ongoing pandemic of Covid 19. The continued development of science and products of vaccinology is necessary for further impact on human life. The development of a strong public health infrastructure by nations around the world is the key to improve upon current efforts at public awareness, proactive interventions and appropriate vaccine utilization during all times. Preparedness for epidemics and pandemics would then become more and more efficient than currently in existence.