Coloured transmission electron micrograph (TEM) of the Hepatitis B virus and its naturally occurring antigen. The red spheres (called Dane particles) are the complete virus. Typically Hepatitis B virus occurs in clusters of three types of particles (as seen here): the virus itself, with smaller spheres and rod-shaped forms made from the protein coat of the virus. The smaller non- infectious spheres (green) are antigenically identical to the virus, & provide raw material for Hepatitis B vaccines. Infection is more serious than Hepatitis A, can be sexually transmitted, & cause the chronic form of hepatitis. Magnificat- ion: x64,000 at 6x4.5cm size.