Human Herpesvirus 6: The Virus and the Search for Its Role as a Human Pathogen; The Pestiviruses; Lactate Dehydrogenase-Elevating Virus, Equine Arteritis Virus, and Simian Hemorrhagic Fever: A New Group of Positive-Strand RNA Viruses; Translational Suppression in Retroviral Gene Expression; Molecular Biology and Genetics of Neurodegenerative Diseases Caused by Prions; Cucumber Mosaic Virus; New Plant Virus Problems in Developing Countries: A Corollary of Agricultural Modernization; Prospects for Oral Vaccination Using Recombinant Bacteria Expressing Viral Epitopes.