(BPT) - The theory behind vaccines — that limited exposure to a disease may help inoculate against more severe illness — has circulated for centuries. In 16th century China, smallpox scabs were ground up and blown into people’s noses to shield them from the disease. While this strategy wasn’t successful, a similar one soon would be.[1] In 1796, the English physician Dr. Edward Jenner created the first real vaccine relying on the limited exposure theory. Dr. Jenner believed an infection with cowpox would protect people from smallpox.[2] He was right. The smallpox vaccine ended what had been a long and tragic battle against a disease that killed 30 percent of those infected, all the way back to when it first emerged in ancient Egypt.[3]

Dr. Jenner’s success paved the way for Louis Pasteur’s rabies vaccine almost a century later,[4] followed by vaccines for other life-threatening diseases such as whooping cough, diphtheria, tetanus, influenza and mumps. Manufacturing advances made it possible to produce large quantities of vaccines, leading to global immunization and vaccination for some diseases and helping to eradicate additional diseases worldwide.