Smallpox Great Britain it became the dominant form of smallpox, further reducing mortality rates. The English physician Edward Jenner demonstrated the effectiveness of cowpox to protect humans from smallpox in 1796, after which various attempts were made to eliminate smallpox on a regional scale. In Russia in 1796, the first child to receive this treatment was bestowed the name "Vaccinov" by Catherine the Great, and was educated at the expense of the nation. The introduction of the vaccine to the New World took place in Trinity, Newfoundland in 1800 by Dr. John Clinch, boyhood friend and medical colleague of Jenner. As
Smallpox vaccine lost its potency at ambient temperatures which restricted its use in tropical climates. However, it remained in use into the 1970s where a satisfactory cold chain was available. Animals continued to be widely used by vaccine producers during the smallpox eradication campaign. A WHO survey of 59 producers, some of whom used more than one source of vaccine, found that 39 used calves, 12 used sheep and 6 used water buffalo, whilst only 3 made vaccine in cell culture and 3 in embryonated hens' eggs. English vaccine was occasionally made in sheep during World War I but from 1946 only