Orthopoxvirus inclusion bodies are aggregates of stainable protein produced by poxvirus virions in the cell nuclei and/or cytoplasm of epithelial cells in humans. They are important as sites of viral replication. [1] [2]
Morphologically there are two types of Orthopoxvirus inclusion bodies, Type-A inclusion bodies and Guarnieri bodies. Type-A inclusion bodies are found only in certain poxviruses like cowpox. [3] The Guarnieri bodies are found in all poxvirus infections and their presence is diagnostic. [4] The diagnosis of an orthopoxvirus infection can also be made rapidly by electron microscopic examination of pustular fluid or scabs. However, all orthopoxviruses exhibit identical brick-shaped virions by electron microscopy.[ citation needed ]
Guarnieri bodies are named for Giuseppe Guarnieri, (1856–1918) an Italian physician who first described them. [5]