Fostering Further Successes in Vaccinology.

Vaccination—preparing or harnessing the power of the human immune system to prevent infectious diseases—is one of the most impactful developments in the history of public health. In more than two centuries of clinical use, vaccines have been responsible for preserving the health and preventing the deaths of millions of children and adults annually. There are several examples in which the widespread and routine use of vaccines has greatly reduced or eliminated infectious diseases from selected geographic regions or hemispheres of the globe. Vaccines enabled the eradication of naturally occurring smallpox from the world—a remarkable achievement with neither precedent nor peer in the realm of medicine. Yet despite the proven track record of vaccine safety and effectiveness, there remain several significant barriers that impede their further development, acceptance, and broader implementation. There is clear evidence that vaccines prevent illness, hospitalization, and death and that their use promotes economic savings through medical and social costs avoided. However, their favorable impact has made vaccine-preventable diseases less common and thus, less visible. The commonly applied outcome metrics used when making the case for investments in vaccines become far less important to policy-makers, the public, and to parents when the preventive measures work and over time, the benefits provided by vaccines become less visible and compelling. For many in the developed world, including physicians, the vaccine-preventable, classic scourges of childhood such as polio, pertussis, diphtheria, measles, and mumps primarily represent historical footnotes. But before the advent of safe and effective vaccines, these infectious diseases caused significant morbidity, mortality, and lingering fear in communities.