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Inoculation

Inoculation, originally Variolation, was a method of minimising the harm done by infectionwith smallpox(Variola). It preceded vaccination- though today popular usage may speak of inoculation and vaccination more or less interchangeably when referring to the process of immunizationagainst disease. The microorganisms and substances used in an inoculation are called inoculant or inoculum.

Inoculation is generally performed by rubbing material from a smallpox pustule from a selected mild case - Variola Minor - into a scratch on the arm. It would not be performed when the recipient was in less than normal good health, and thus at his peak resistance. The recipient would develop smallpox. However, because becuase of th eselection, and perhaps because the infection did not take place by the normal route of infection, a particularly mild form of smallpox developed, which had a far lower mortality ratethan catching smallpox in the normal way, and left an immunity to later re-infection. The inoculated subject also usually recovered from the infection with far less facial scarring than occurred with naturally acquired smallpox.

The earliest use of the practice remains unknown. It had occurred in various manners in East Africa, Indiaand in Chinafor centuries, but documentation exists of its adoption in western Europe. In the early 18th century, Lady Mary Wortley Montagu, whose husband Edward Wortley Montaguserved as the Englishambassadorto the Ottoman Empirefrom 1716 to 1717, witnessed inoculation in Constantinople. The process impressed her greatly: she had lost a brother to smallpox and bore scars from the disease herself. In March 1718she had the embassy surgeon, Charles Maitland, inoculate her five-year-old son. In 1721, after returning to England, she had her four-year-old daughter inoculated. She invited friends to see her daughter, including Sir Hans Sloane, the King's physician. Sufficient interest arose that Maitland gained permission to test inoculation on six condemned prisoners at Newgate prison, witnessed by a number of notable doctors. The trial succeeded; the prisoners gained their freedom, and in 1722 the Prince of Wales'daughters received inoculations.

The practice of inoculation slowly spread amongst the royal families of Europe, usually followed by the more general adoption amongst the people. As early as 1732the practice is documented in America. Fearing the outbreak of an epidemic, the editor of the South Carolina Gazette published a detailed description of the innoculation process in the April 22 issue. J.Z. Holwelldescribed the Ayurvedicsystem of inoculation against smallpox to the Royal College of Physiciansin Londonin 1767in a tract called An account of the manner of inoculating for the small pox in the East Indies. He based his account on observations made during his residence in Bengal.

In Franceconsiderable opposition arose to the introduction of inoculation: Voltaire, in his Lettres Philosophiques wrote a criticism of his countrymen for having so little regard for the welfare of their children (English translation on-line[1]).

Given the prevalence of smallpox in the 18th century (60% incidence of first infection, 20% mortality 20% severe scarring. Voltaire), one could expect almost inevitably to become infected by it sooner or later. The advantages of inoculation seemed so evident that parents would pre-empt the dangerous natural infection by the less risky use of inoculation; but Edward Jenner's introduction of the far safer cowpoxin vaccination after 1796 eventually led to the smallpox inoculation falling into disuse.

Inoculation

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