Virus Taxonomy Online: (A) Diagram of a virion section with lipid membranes, capsid and nucleoprotein core visualized of African swine fever virus (ASFV) particle. (B) Thin section, (C) cryo-section and (D) a negative contrast electron micrograph of ASFV particles. The arrows indicate the membrane components of the virus; pm = plasma membrane. (EMs were provided by Dr Sharon Brookes, IAH Pirbright.) The bar represents 200 nm.