Immunization and vaccination
The Fundamentals of Immunization (Magill’s Medical Guide, Sixth Edition)
The major day-to-day function of the immune response is to protect the body from infection. Exposure to foreign antigens such as infectious agents results in the stimulation of either of two components of the immune system: the humoral (or antibody) immune response or the cellular immune response. Although no clear division exists between these two facets of the immune system, the antibody response deals primarily with organisms such as bacteria that live outside the cell. The cellular response deals primarily with microbes that live within a cell, such as intracellular bacteria or viruses.
A specialized class of white cells called B lymphocytes carries out the production of antibodies. Stimulation of these cells results from a complicated interaction between a variety of cells, including antigen-presenting cells (macrophage and dendritic cells) and both T and B lymphocytes. The response is specific in that each type of T or B cell can interact with only a single antigen. The B cell that produces antibodies against a particular characteristic or shape on the surface of a bacterium reacts only with that particular determinant. In turn, the antibodies secreted by that B cell can interact only with specific determinants.
Antibodies secreted by B cells are themselves inert proteins. A variety of effects can result, however, when an antibody binds to an antigen. The specific results depend on the nature of...
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History and Major Successes (Magill’s Medical Guide, Sixth Edition)
Since the first use of vaccination by Jenner in the 1790’s for the prevention of smallpox, immunization techniques have been developed for protection against most major infectious illnesses. The term “vaccination” was originally applied to immunization against smallpox, but its definition has long been expanded to include most immunization techniques. The terms “vaccination” and “immunization” are used interchangeably, although there are technical differences in their definitions.
The nineteenth century improvements in public health measures, combined with the passage of laws for compulsory vaccination, resulted in a steady decrease in the number of smallpox cases in the United States and most countries of Europe. Even as late as 1930, however, approximately 49,000 cases were reported in the United States. In the 1950’s, large numbers of cases were still being reported in areas of Africa and Asia. At that time, the World Health Organization (WHO) of the United Nations decided on a plan for the elimination of smallpox based on the fact that humans served as the sole reservoir for the smallpox virus; animals are not naturally infected with smallpox. Through the use of mass immunization techniques, the plan was to isolate areas of infection into smaller and smaller pockets.
The plan for the elimination of smallpox developed by WHO ultimately proved completely successful. There are actually two...
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Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
The elimination of smallpox represents the classic example in which the efficacy of a vaccine resulted in the eradication of disease. Smallpox was an ancient disease, with origins as early as the twelfth century b.c.e. It appeared in the Middle East in the sixth century c.e., with subsequent dissemination into northern Africa and southern Europe as a result of the Arab invasions from the sixth to the eighth centuries. The disease spread throughout Europe during the Crusades of the eleventh and twelfth centuries and reached the Americas as a result of the African slave trade in the sixteenth century. It has been estimated that, at its peak during the eighteenth century, smallpox killed 400,000 persons each year and caused more than one-third of all cases of blindness. It has also been estimated that smallpox or other diseases killed approximately 85 percent of the American Indians who died during colonial periods, certainly far more than the number who died from bullet wounds.
The principle of immunization in prevention did not originate with Jenner, the English physician credited with development of the smallpox vaccine in the 1790’s. A practice called variolation was well known in China and parts of the Middle East for centuries prior to Jenner. Variolation consisted of the inhalation of dried crust prepared from the pocks obtained from individuals suffering from mild cases of smallpox. A variation involved...
(The entire section is 989 words.)
For Further Information: (Magill’s Medical Guide, Sixth Edition)
Behbehani, Abbas. The Smallpox Story in Words and Pictures. Kansas City, Mo.: University of Kansas Medical Center, 1988. The book includes the history of Edward Jenner and his use of cowpox in the first smallpox vaccine. The drawings and photographs are of particular interest.
Brock, Thomas D., ed. Microorganisms: From Smallpox to Lyme Disease. New York: W. H. Freeman, 1990. A collection of readings from Scientific American magazine. Included is a section on the role of vaccines in the prevention of disease, including their role in the elimination of smallpox. Also found are articles on synthetic vaccines and vaccination in the developing world.
Delves, Peter J., et al. Roitt’s Essential Immunology. 11th ed. Malden, Mass.: Blackwell, 2006. An excellent textbook on the subject of immunology. Much of the book is detailed and requires some background in biology. Nevertheless, the chapters that deal with infection and immunization are clear and contain much that will interest nonscientists. Numerous graphs illustrate material from the text.
Grandi, Guido, ed. Genomics, Proteomics, and Vaccines. Hoboken, N.J.: John Wiley & Sons, 2004. The authors begin with a history of vaccine development and proceed with both classical methods and a description of how new generations of vaccines have built upon biotechnology. Best appreciated by those with a science...
(The entire section is 399 words.)