The story of vaccines started long before recorded history. We are naturally designed to acquire immunity to pathogens that we are exposed to, that we recover from after falling ill. Ancient civilizations observed this phenomenon and attempted artificial immunization in a form that is the basis of modern-day immunization. Evidence exists that the Chinese employed smallpox inoculation as early as 1000 AD; it was also practiced in Africa and Turkey long before its spread to Europe and the Americas. The practice of vaccination can result in both naturally acquired Active immunity or Passive immunity. The question is how the ancient civilizations managed to balance the risk of death from immunization and its potential lifesaving benefits. 

There is no evidence that the ancients attempted to weaken a pathogen before infecting healthy people with it to initiate an immune response, resulting in acquired immunity against a pathogen.  In fact evidence suggest, that this practice is done as a last resort against a pathogen capable of causing severe mortality in a population. In this case those who will be inoculated should be of robust health; well fed, well rested and diet supplemented with immune boosting herbs. It was not until Edward Jenner’s (No relation to Caitlyn Jenner) discovery that humanity truly embraced the concept of vaccination. Edward Jenner’s innovations, begun with his successful 1796 use of cowpox material to create immunity to smallpox. The idea that you can use a weak form of a pathogen to offer immunity against a more serious infection, quickly made the practice widespread. His method underwent medical and technological changes over the next 200 years, and eventually resulted in the eradication of smallpox.

Louis Pasteur’s 1885 rabies vaccine was the next to make an impact on human disease. Then, at the dawn of bacteriology, developments rapidly followed. Antitoxins and vaccines against diphtheria, tetanus, anthrax, cholera, plague, typhoid, tuberculosis, and more were developed through to the 1930s. The middle of the 20^th century was an active time for vaccine research and development. Methods for growing viruses in the laboratory led to rapid discoveries and innovations, including the creation of vaccines for polio. Researchers targeted other common childhood diseases such as measles, mumps, and rubella, and vaccines for these diseases reduced the disease burden greatly. However in this race to mass produce vaccines, many short cuts were made and maybe it was due to financial gains, or an eagerness to lead the field in vaccine creation that has led to our modern day mistrust of vaccines. 

Motor vehicles were not abandoned because of the high mortality associated with motor vehicle accidents. Instead, there was a push to make vehicles safer and now airbags, and seatbelts are a must in all new vehicles. Similarly, vaccine manufacture can be made safer to minimise the side effects when things go wrong. We can pressure our politicians to demand stringent vaccine manufacturing practices, where the goal is not the volume of a vaccine that can be mass produced in a short space of time, but the purity of the vaccine to reduce the risk of vaccine related adverse reactions.

Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response. ... Immunizations are successful because they utilize the immune system's natural specificity.

Passive immunization involves the production of antibodies in one animal by active immunization. These antibodies can be stored (as immunoglobulins) and then administered to susceptible animals to confer immediate but short-lived protection. The transfer of maternal antibody to offspring via the placenta or colostrum is the natural (and very important) form of passive immunization.