Hepatitis A virus. Coloured transmission electron micrograph (TEM) of a cluster of Hepatitis A virus particles, the cause of infectious hepatitis. The particles are made of a protein coat encapsulating ribonucleic acid (RNA) genetic material. During Hepatitis A infection, the virus attacks the liver producing liver inflammation, fever and jaundice. Hepatitis A may be transmitted person-to-person via the faecal/oral route. The virus may, on occasions, be transmitted by faecally contaminated food or water. The disease is more prevalent in warm countries with poor standards of hygiene. Magnification: x164,000 when printed 10 centimetres wide.