Vol. 6, Issue 2, Part A (2024)

The discovery of vaccination and the eradication of smallpox from the planet are among the greatest achievements in the history of humanity, and represent a major step forward in the development of immunology. The presence of various mechanisms in the body to interact with invading microorganisms makes an immune system effective. This immune system plays an important role in preventing infections, eradicating overt infections and preventing tumor proliferation. Innate immunity, also known as natural immunity, corresponds to a constitutive response with immediate, non-adaptive action. Adaptive or acquired immunity is antigen-specific. The adaptive response is limited in time to the eradication of the aggressor whose memory it retains. Vaccination is a means of protecting an organism against disease by stimulating the immune system at an early stage. Despite significant progress in vaccination, which has led to exceptional success in protecting the health of populations, there are major gaps in knowledge and challenges to be overcome. An incomplete understanding of the immune mechanisms of protection has hampered the design of appropriate vaccines. In other words, infection plays an important role in the establishment of an effective immune response and interventions such as early vaccination could make a significant contribution to the fructification of this response. This review provides an overview of the different immune responses that the body employs to counter infections. The strategies adopted for effective vaccination will be discussed. The principle of vaccine therapy and antimoral immunotherapy will also be examined.