During this period there were no adequate methods for assessing the safety of the vaccine and there were instances of contaminated vaccine transmitting infections such as erysipelas, tetanus, septicaemia and tuberculosis. In the case of arm-to-arm transfer there was also the risk of transmitting syphilis. Although this did occur occasionally, estimated as 750 cases in 100 million vaccinations,: 122  some critics of vaccination e.g. Charles Creighton believed that uncontaminated vaccine itself was a cause of syphilis. Smallpox vaccine was the only vaccine available during this period, and so the determined opposition to it initiated a number of vaccine controversies that spread to other vaccines and into the 21st century.Sydney Arthur Monckton Copeman, an English Government bacteriologist interested in smallpox vaccine investigated the effects on the bacteria in it of various treatments, including glycerine. Glycerine was sometimes used simply as a diluent by some continental vaccine producers. However, Copeman found that vaccine suspended in 50% chemically pure glycerine and stored under controlled conditions contained very few "extraneous" bacteria and produced satisfactory vaccinations. He later reported that glycerine killed the causative organisms of erysipelas and tuberculosis when they were added to the vaccine in "considerable quantity", and that his method was widely used on the continent. In 1896, Copeman was asked to supply "extra good calf vaccine" to vaccinate the future Edward VIII.Vaccine produced by Copemans method was the only type issued free to public vaccinators by the English Government Vaccine Establishment from 1899.
By 1800, Jenners work had been published in all the major European languages and had reached Benjamin Waterhouse in the United States – an indication of rapid spread and deep interest. : 262–67  Despite some concern about the safety of vaccination the mortality using carefully selected vaccine was close to zero, and it was soon in use all over Europe and the United States. In 1804 the Balmis Expedition, an official Spanish mission commanded by Francisco Javier de Balmis, sailed to spread the vaccine throughout the Spanish Empire, first to the Canary Islands and on to Spanish Central America. While his deputy, José Salvany, took vaccine to the west and east coasts of Spanish South America, Balmis sailed to Manila in the Philippines and on to Canton and Macao on the Chinese coast. He returned to Spain in 1806. The vaccine was not carried in the form of flasks, but in the form of 22 orphaned boys, who were carriers of the live cowpox virus. After arrival, "other Spanish governors and doctors used enslaved girls to move the virus between islands, using lymph fluid harvested from them to inoculate their local populations".The first state to introduce compulsory vaccinations was the Principality of Lucca and Piombino on September 25, 1806. On August 26, 1807, Bavaria introduced a similar measure. Baden followed in 1809, Prussia in 1815, Württemberg in 1818, Sweden in 1816, England in 1867 and the German Empire in 1874 through the Reichs Vaccination Act.