The first human vaccines against viruses were primarily based on the exploitation of weaker or attenuated viruses to come back up with immunity. The pox immunizing agent used Vaccinii, associate degree virus that was similar enough to pox to protect against it but generally did not cause serious illness. The madness was the first virus attenuated in a very work to make an immunizing agent for humans. Vaccines unit of measurement created exploitation several utterly completely different processes. they are going to contain live viruses that area unit attenuated (weakened or altered to not cause's illness); inactivated or killed organisms or viruses; inactivated toxins (for being diseases where toxins generated by the bacteria, and not the microorganism themselves, cause's illness); or simply segments of the agent (this includes every unit and conjugate vaccines).
- Track 1-1 Inactivated Vaccines
- Track 2-2 Live-Attenuated Vaccines
- Track 3-3 Toxoid Vaccines
- Track 4-4 Recombinant Vaccines
- Track 5-5 Subunit and Conjugate Vaccines