Morphologically, there are two types of Orthopoxvirus inclusion bodies: Type-A inclusion bodies and
Guarnnier bodies. Type-A inclusion bodies are found only in certain poxviruses like
cowpox. Guarnnier bodies are found in all poxvirus infections and their presence is diagnostic. 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. == References ==