Variolation shortly after variolation began to outweigh the benefits of the procedure. From the 1760s, a number of individuals, including John Fewster, Peter Plett, Benjamin Jesty, and particularly Edward Jenner, were interested in the use of material from cowpox, an animal infection, to protect against smallpox. In 1796, Jenner vaccinated James Phipps, did more vaccinations in 1798, and was the first to publish evidence that cowpox protected against smallpox, was safer than variolation, and that his vaccine could be maintained by arm-to-arm transfer. The use of variolation soon began to decline as the smallpox vaccine became widely used and its benefits
Smallpox the first use of the term "variola"; other historians speculate that Arab armies first carried smallpox from Africa into Southwestern Europe during the 7th and 8th centuries. In the 9th century the Persian physician, Rhazes, provided one of the most definitive descriptions of smallpox and was the first to differentiate smallpox from measles and chickenpox in his "Kitab fi al-jadari wa-al-hasbah" ("The Book of Smallpox and Measles"). During the Middle Ages, smallpox made periodic incursions into Europe but did not become established there until the population increased and population movement became more active during the era of the Crusades. By