Electron microscopy as a tool for identifying new pathogens

Electron microscopy (EM) is still an important tool for the investigation o f infectious diseases, despite the introduction of powerful new methods, ma inly involving the polymerase chain reaction. Particularly in the field of parasitic protozoology associated with AIDS, where many new species of huma n pathogens have been recognized in tissue biopsies, EM remains on essentia l 'catch-all' diagnostic method. The resolved ultrastructural details of th ese newly recognized parasites allows a unique insight into the biology of these organisms. The information produced by EM is different, but complemen tary, to that provided by alternative methods, (C) 2000 The British Infecti on Society.