The Chinese and the Ottomans had been using "variolation
" for centuries, a procedure in which people were deliberately infected with material from smallpox scabs applied inside the nostrils or under the skin.
Although Chinese medical manuscripts provided a wealth of information on the disease and its treatment, it was surprising to see the Vietnamese apathy toward the Chinese method of variolation
in their prevention of smallpox.
(395) Indeed, exposure to low doses of smallpox, the practice of variolation
widely practiced in the eighteenth and nineteenth centuries, (396) was once the preferred means of preventing the disease.
This knowledge was applied as early as the 10th century in China to impart immunity to smallpox by inoculating the uninfected with a small amount of smallpox pus, a process known as variolation
(from the Latin for smallpox, Variola).
Chinese physicians practised variolation
, the transfer of infectious material from patients with mild cases of smallpox to individuals who had yet to contract the disease.
We know more about smallpox, which preventive medicine in the form of variolation
(introduced to the west by Lady Mary Montagu in the early eighteenth century) and vaccination (Edward Jenner, 1798), reduced from being the single biggest killer in eighteenth-century Britain to a minor cause of death by the mid-nineteenth century.
Immunization, for example, has been a staple of deployment readiness since General George Washington ordered variolation
against smallpox for the Continental Army in 1777.
(the use of smallpox scabs from infected individuals to inoculate healthy individuals) was probably first used in China or India in the 11th century and moved to Europe via the Middle East and Turkey.
Deaton suggests the divergence arose from different health habits, with the gentry having the wherewithal to take advantage of fancy and expensive new medical technologies such as variolation
to prevent smallpox and chinchona bark to treat malaria.
But they are proof of concept, something akin to what variolation
was to modern vaccinations.