From the beginning of times, humankind has faced all sorts of life-endangering situations, threats, and illnesses. Thus, has been constantly trying to come up with new ways to preserve the species and keep sickness away or at least under control.
Although it was not new to expose an individual to the sickening pathogen in a small dose to inoculate it, formal vaccination was introduced at the end of “The Century of Lights”. Through rabies, diphtheria, Spanish flu, yellow fever, polio, and a wide variety of illnesses, vaccines have enormously evolved and successfully eradicated and prevented many health problems.