Coloured transmission electron micrograph (TEM) of a single Nipah virus particle (centre, green) that has budded from the surface of an infected cell (pink). The virus has been immunolabelled using antibodies that attach to viral envelope proteins and have gold particles (gold spheres) attached to them. Nipah virus is zoonotic (transmitted to humans from animals) and has been associated with encephalitis (inflammation of the brain). Nipah virus infection is characterised by fever and drowsiness and more serious central nervous system disease, such as coma, seizures and an inability to maintain breathing. It was first described in Malaysia and Singapore in pig farmers but is also found in the wild in bats. Image obtained at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland, USA.