Toby K. Eisenstein Symposium Committee Chairperson Temple University School of Medicine Philadelphia, Pennsylvania 19140 This symposium is the thirteenth biennial clinical microbiology program sponsored by the Eastern Pennsylvania Branch of the American Society for Microbiology in cooperation with the Philadelphia area medical schools and the Bureau of Laboratories of the Pennsylvania Department of Health. This year a generous contribution from Merck, Sharp and Dohme has helped to make the program a reality. The subject matter for this symposium represents an attractive spectrum of medical, biological and molecular approaches to the practical solution of a public health prob1em--name1y, prevention of infection with the hepatitis B virus. The symposium may be unique in that it focuses on a product which was first marketed less than three months ago, but included in the program are presen­ tations on two new approaches to hepatitis B vaccine production which may replace the one which is newly unveiled. The rapidity of progress in our present era of biological research is indeed astonishing.

Keynote Address: The Australia Antigen Story.- The Virus and Its Transmission.- Hepatitis B Viruses.- Medical Consequences of the Carrier State.- The Epidemiology of Hepatitis B.- Clinical and Diagnostic Perspectives of HBV.- The Morphologic Expression of Hepatitis B.- Assays for Hepatitis B Virus.- Immunologic Responses to Hepatitis B Virus and their Interpretations.- Hepatitis B Infection Control Among Physicians, Dentists and Laboratory Personnel.- Control Measures for Hepatitis B Problems in Dentistry.- The Vaccine.- The Development of the Hepatitis B Vaccine.- Clinical Experience with Hepatitis B Vaccine.- Hepatitis B Vaccine Trials, Experience and Review.- Priorities for the Use of Hepatitis B Vaccine.- Vaccine Economics: Issues and Answers.- Newly Licensed Hepatitis B Vaccine.- Vaccines of the Future.- Characterization and Mapping of Viral and Putative Viral-Cellular Transcripts in a Hepatitis B Virus Infected Human Hepatoma Cell Line and in Chimpanzee Carrier Liver.- Hepatitis B Surface Antigen Polypeptide and Synthetic Peptide Vaccines.- Synthesis and Assembly of Hepatitis B Virus Antigens in Heterologous Systems.- Closing Remarks.- Abbreviations.- Contributors.