Hantavirus. Coloured transmission electron micrograph (TEM) of a hantavirus. This causes haemorrhagic fever with renal syndrome (HFRS) or Hantavirus pulmonary syndrome (HPS). The virus contains ribonucleic acid (RNA) genetic material that is held inside a protein coat (capsid, red). Surface proteins (green) are seen on the capsid. Humans become infected by inhaling or ingesting excreta from infected rodents. The symptoms range from fever and muscle weakness (myalgia) to haemorrhage and cardiovascular instability, which can lead to death. Magnification unknown.