title: Epidemiology of the delta agent: an introduction.
mesh_terms: D000818:Animals; D003673:Defective Viruses / Q000472:pathogenicity; D006509:Hepatitis B / Q000382:microbiology; D006511:Hepatitis B Antigens / Q000032:analysis / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006518:Hepatitis Viruses / Q000472:pathogenicity; D035923:Hepatitis delta Antigens; D006525:Hepatitis, Viral, Human / Q000453:epidemiology*; D006801:Humans; D002679:Pan troglodytes
chemical_list: D006511:Hepatitis B Antigens; D006514:Hepatitis B Surface Antigens; D035923:Hepatitis delta Antigens