A method for increasing the surface details of resin embedded viruses using Congo/Crimean haemorrhagic fever virus as a model.

The surface details of resin embedded viruses can be greatly enhanced by the use of uranyl acetate block staining. The virions are embedded in agar immediately after fixation and block stained with 3% uranyl acetate in methanol during dehydration. This technique allows those particles outside their host cells to show clearly the spikes normally seen only by the separate use of negative staining.