This Centennial Meeting is an appropriate occasion to celebrate the important role American pediatrics has played in bringing a number of important viral diseases under control. Preventive medicine has been a major activity of the American Pediatric Society and its members have made a disproportionately large contribution to the development of safe, effective viral vaccines.

Currently, effective licensed vaccines are available for prevention of disease caused by 10 distinct human viruses or viral groups. The first of these vaccines, vaccinia virus, was developed by Jenner 190 years ago for the prevention of smallpox. Ninety years elapsed until the rabies virus vaccine was developed by Pasteur. During the last 50 years, the pace of discovery and development accelerated and vaccines for eight additional viruses or virus groups were added to our armamentarium. Members of the American Pediatric Society played an essential role in the development of vaccines for five of these eight viruses or virus groups: inactivated poliovirus vaccine, John Enders, Thomas Weller, and Frederick Robbins; live poliovirus vaccine, Albert Sabin; live measles virus vaccine, John Enders and Samuel Katz; live rubella virus vaccine, Hany Meyer and Stanley Plotkin; live adenovirus vaccine, Robert Chanock; and inactivated hepatitis B virus (HBV) vaccine, Saul Krugman. It should be noted that eight of the 10 viral diseases against which effective vaccines are now available are caused by viruses that produce a systemic infection. This is not surprising because small amounts of serum antibodies are usually highly effective in preventing disease caused by viruses that spread systematically. In contrast, the requirements for effective immunization against a topical infection in which virus produces its disease manifestations at the site of implantation are more demanding because locally produced mucosal antibodies and/or a high concentration of serum antibodies are needed for resistance.