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
History of smallpox in Mexico 1799. Viceroy Miguel José de Azanza, ordered an article written on 14 November 1799 about the benefits resulting from the inoculation in the 1790s epidemic and distributed to the population. In 1803, Spanish doctor Francisco Javier Balmis started a vaccination program against smallpox in New Spain, better known as Balmis Expedition, which reduced the severity and mortality in the epidemics that followed. Before Balmis, Dr José María Arboleyda started a vaccination campaign in 1801 but this was not successful. There was another important outbreak in 1814 which started in Veracruz and extended to Mexico City, Tlaxcala and Hidalgo. This epidemic