Diseases can be tackled by medicine and other treatments, and that is because of the revolution and progress in medicine today. But, diseases have been infiltrating human health since ages, even before the research and invention of medicines. So what did people do back then? Since centuries, or ever since the evolution of mankind, certain diseases have been attacking, and killing many people every year. Among the deadliest diseases history has seen across the globe, smallpox, is one name that cannot be forgotten. We all have information on smallpox, but are not aware of its history. This disease spread like wild in the 18th century and was spreading waves of infection in many countries. Smallpox is an infectious viral disease, that was caused by 'Orthopox variola '. It is known that mankind saw the fierce killer thousands of years ago. Since then, it was known that smallpox survivors were immune to any further infection from the virus. Considering this theory, many healthy people were treated with dried, powdered scabs of the smallpox, so as to induce immunity against the virus. This was known as 'inoculation'. It was observed that people developed a mild disease due to this method, but they did not catch the deadly virus. Mortality rate too was very less (1-2%) as compared to the infection that killed people. This was perhaps the beginning, let's understand, the history of this vaccine in detail. Now the methods of inoculation were tried and tested on many people and which also showed convincing results. This method spreads across many countries and inoculation became the preventive measure against smallpox. This later came to be known as variolation. This became very popular, most of the cases saw an improvement in the health and recovery, while few cases reported death due to the disease. There was no demand for the treatment for smallpox then, so most of the physicians got into inoculation. The mortality rate was very low and it also gave people assurance of immunity against the infection. This practice grew in the European states and other countries as well, but it also drew a lot of controversies, as during the trials, many epidemics broke in, and the variolation though effective, still saw the disease spread like wildfire. In 1757, inoculation was carried out for many children in England. In Gloucester, an eight year old boy was inoculated, who was among the thousands of other children inoculated. This boy developed a mild disease and later got immune to the same. This child proved to be the next savior of the world from smallpox, with the introduction of this vaccine. Let us know how, in the following. Invention of the Smallpox Vaccine This boy who was inoculated among the thousands in England was Edward Jenner. He grew up to become a scientist and has credits on the invention of the smallpox vaccine. He took note of the knowing, that milk maids that contracted cowpox, which is a mild disease, were immune to smallpox. Considering this theory, he inoculated an eight year old boy with cowpox. Cowpox too is known to be caused by a similar virus like that of variola. Now after this inoculation, the boy showed immunity to smallpox even after deliberate exposure to the virus. This was the time, it was observed that not only does cowpox when contracted protect you from smallpox, but it can also be used as a protective and preventive option. This was later experimented on another person, where, the cowpox was taken from a lesion on the hands of a milk maid, and inoculated in the healthy person. The experiment was a success. Cowpox created immunity against smallpox, that too with very few side effects and decreased mortality rates as compared to variolation. This is when, the vaccine for was invented. The vaccine word comes from 'vacca' which means 'cow' in Latin. This vaccine gained a lot of importance, and helped in eradication of this dreaded infection. Smallpox later was completely eradicated in the year 1979, after the global campaign of WHO (World Health Organization) in 1967, which slowly wiped out this disease. This is a great achievement in health and medicine. With all these facts, we conclude this article on history of smallpox vaccine, which surely portrays the fight of mankind, which won with the complete eradication of this infectious disease.