Immunization update and hot topics in clinical immunology: how does this relate to my practice?

The prevention of infectious diseases by the use of vaccines represents one of medicine's greatest triumphs during the 20th century. This era has witnessed the global eradication of smallpox as a result of Jennerian cowpox vaccination, the elimination of paralytic poliomyelitis from the western hemisphere, and within 5-10 years the anticipated eradication of poliomyelitis worldwide as a result of the poliovirus vaccines. Next slated for worldwide eradication is measles, the great killer of infants and children, which each year extracts a global mortality of one million victims. Throughout the 20th century the percutaneous (i.e., subcutaneous or intramuscular) route has almost exclusively been the preferred way to administer vaccines. However, as a result of several important scientific discoveries made during the 20th century, including new tissue-culturing techniques, the development of recombinant DNA technology, and genetic sequencing, a whole new generation of tailor-made modern vaccines has become available, including DNA vaccines and transgenic plant vaccines. Moreover, it became apparent that alternative routes of administration of vaccines, such as by aerosol immunization might be more appropriate and more effective than immunization via the parenteral route. The overall success in vaccine development, however, has not been without cost. For every new vaccine that has been developed, an adverse effect has been seen. Thus, although modern vaccines are extremely safe and effective, they are neither completely safe nor completely effective. The goal of vaccine development, therefore, is to achieve the highest degree of protection and the lowest rate of adverse effects. This paper describes some of the recent advances in vaccine development and will focus on some hot topics relating to the recent development and use of respiratory aerosolized vaccines.