The electron microscopy (EM) unit of the Leibniz-IZW is a central facility within the institute and open to all research groups as well as to external collaborators. The Leibniz-IZW has two electron microscopes: A transmission electron microscope (“Tecnai G2 Spirit BioTWIN”, 120 kV, FEI) equipped with a side mounted 2k (Veleta, Olympus-SIS) and a bottom mounted 4k (TIA, FEI) digital camera and a field emission scanning electron microscope (“Gemini Supra 40 VP“, Zeiss). They enable us to investigate finest structures of the smallest dimension in high resolution. Routinely, TEM samples are resin-embedded for ultra-thin sections, but immuno-EM can also be performed. For the investigation of possible viral infections, negative staining of homogenised fresh tissue or faecal samples is applied. Thanks to a variable pressure mode of the scanning electron microscope, fresh samples can be visualised without fixation or conductive coating.