Variolation

    Smallpox as an acute and highly contagious disease had inflicted disastrous damage on humanity. In mankind's fight against this epidemic virus, variolation marked a breakthrough. This great achievement in immunology was scored by Chinese no later than the 16th" century. Variolation and vaccination finally led to the eradication of this fatal disease as declared by the World Health Organization in 1979.

    Variolation came as a result of the Chinese tradition of disease prevention. In The Book of Changes, The Yellow Emperor's Canon of Internal Medicine and other classics, there were quite a few ideas about disease prevention: "The wise man should pay attention to the prevention of diseases." "An excellent doctor usually treats people before they apparently fall ill, therefore illness rarely occurs." "Is not it too late to administer drugs when illness has developed?  By detecting delicate changes, a good doctor is able to treat a patient as early as possible to cure the disease and help the patient recover." Chinese doctors also developed the concept of "combating poison with poison." Ge Hong (c.281- 341), a well-known doctor of the 3~a century, used to cut a piece of the brain of a killed mad dog to cover the wound of the patient who was bitten by the dog, intending to prevent rabies. Sun Simiao (581-682), a celebrated medical scientist of the 7th century, transferred with a small knife the blood and pus of a patient with ulcer to healthy people under the skin as a means of prevention. These were only some of the experiments and practices in immunology in ancient China.

    Smallpox was said to have spread to China from the south in the 2nd century. Chinese doctors made great efforts to fight and prevent the dreadful disease. When did the Chinese invent variolation? The answer to this question has three versions: A person surnamed Zhao of the Tang Dynasty invented it in the 8th century; doctors at Mount Emei in Sichuan in the Song Dynasty developed the method in the l]th century; and people in Anguo of Anhui Province in the Ming Dynasty practiced variolation in the 16th century. In all the three versions, the principle of combating poison with poison was followed: to infect people with substance from pustules of smallpox patients in order to boost their immunity to the fatal disease. Scholars tend to accept the third version, but they also acknowledged that the first two were not necessarily groundless.

     Emperor Kangxi of the Qing Dynasty contributed a great deal to the popularization of variolation. In 1681, Emperor Kangxi sent envoys to Jiangxi Province in the south to recruit doctors practicing variolation. Zhu Chungu became the first doctor sent by the emperor to inoculate the children of Manchu and Mongol officials in the Northeast and Khalka. The effort met with a great success. Emperor Kangxi later commented, "In the beginning of this dynasty, people were very afraid of smallpox. When i got the method of variolation, your children have been protected from the disease. I ordered the practice to be carried out in the 49 banners in the Northeast and all the feuds in Khalka. All people inoculated are well protected. I still remember that when this was first done, many elderlies were quite surprised. I have insisted in it, and thousands upon thousands of people have been saved." Zhang Yah, a contemporary of Zhu Chungu, reported, "I have variolated more than 9,000 people, and the failures numbered only 20 to 30." This shows that the rate of success was 97 to 98 percent.

    Thanks to Emperor Kangxi's decision, the spread of smallpox was curbed in China. When the good news reached other countries, Russia sent doctors to China to learn the technique in 1688. The method was popularized in England in 1721-1722 by Lady Mary Wortley Montagu, and won the support of the Queen.

    The technique of variolation spread in the 17th century from China to the Americas, as well as to Japan and Korea, where it was popularized in the early 18th century. In 1796 the British physician Edward Jenner (1749-1823) discovered vaccination, and used the cowpox virus to confer protection against smallpox, a related virus, in humans. Vaccination was introduced to China in 1805. Both vaccination and variolation have contributed to the elimination of smallpox in the world.