Type D (delta) hepatitis.

In the ten years since the delta agent was discovered, major advances have been made in the understanding of its structure, genomic organization, replicative cycle, clinical course, and epidemiology. The recent breakthroughs in cloning of the HDV genome and development of animal models for study of this agent promise to transform these advances in knowledge to advances in means of prevention and therapy for this severe form of acute and chronic liver disease.