Development of vaccines

The roots of modern immunization can be traced back hundreds of years to early attempts to derive protection from disease through exposure to the putative cause. Buddhists in seventh-century India drank snake venom to protect against the deadly effects of a snakebite in what may have been an attempt to induce immunity. Variolation - the introduction of dried pus from smallpox pustules of a mild case into the skin of an unaffected person - as a regular practice dates back at least to sixteenth-century India, although it appears to have developed in Central Asia as early as the second century and then spread to China, Turkey, and eventually to Europe in the eighteenth century (Plotkin and Orenstein, 2004).

Edward Jenner's work on smallpox ushered in the modern vaccine era. Although his accomplishments built on the work of others - most notably that of an English cattle breeder named Benjamin Justy - and on earlier observations that cowpox infection provided immunity against smallpox, Jenner is considered the father of modern immunization because he took a systematic, scientific approach to vaccination and the understanding of immunity, and presented his findings for peer review to the community of physicians and scientists. The results of his experiments demonstrating the effectiveness of systematic cowpox inoculation in the prevention of smallpox were published in 1798 in his work entitled Variolae Vaccinae (Plotkin and Orenstein, 2004).

Louis Pasteur built on the work of Jenner to lay the foundation of modern vac-cinology through his research on attenuation and the application of this principle to the development of vaccines against rabies, cholera, and anthrax. His work was also seminal because he demonstrated that standardized, reproducible vaccines could be produced in large quantities (Plotkin and Orenstein, 2004). The Institut Pasteur, established in 1887 to further Pasteur's work on rabies vaccine and the study of infectious disease, remains a leader in the fields of microbiology, immunology, and molecular biology (Institut Pasteur, 2006). Its academic research model and its collaboration with industry and the public sector to move discoveries from the bench to the bedside are enduring legacies that reflect the complex fabric of interconnected partnerships that is the modern vaccine enterprise.

This early history of immunization was also characterized by another important and enduring factor - public controversy. Two noteworthy early immunization advocates were, in England, Lady Montagu, and in the United States, Thomas Jefferson. Lady Mary Wortley Montagu, the wife of the British Ambassador to Constantinople, is credited with introducing variolation to England upon her return in 1721. She was an enthusiastic and persuasive advocate of the practice as a result of her own experience of smallpox, which had left her scarred (Glynn and Glynn, 2004; Plotkin and Orenstein, 2004). Her efforts resulted in variolation of the British army, which likely played a role in their defeat of the Americans at the battle of Quebec - an outcome that assured that Canada remained within the British Empire (Glynn and Glynn, 2004). Thomas Jefferson, a renaissance man whose passions extended to science and the prevention of disease, collaborated with Benjamin Waterhouse to research and promote smallpox vaccination. Waterhouse, a professor at Harvard Medical School who had trained in Europe, is credited with bringing smallpox vaccination to the United States. When unsuccessful in convincing President John Adams to support his smallpox immunization efforts, Waterhouse turned to Vice-President Jefferson for assistance. Jefferson, understanding the importance and the immense potential of smallpox vaccination, not only supported Waterhouse's efforts; he also conducted surveillance and immunizations himself, introducing smallpox vaccination to Virginia, Washington DC, and Philadelphia. He continued to promote immunization as President, and summarized the importance of these efforts in an 1806 letter to Edward Jenner in which he wrote: "{f}uture nations will know by history only that the loathsome smallpox has existed and by you has been extirpated" (Leavell, 1977).

0 0

Post a comment