General Properties of Major Animal Virus Groups

Groups - Nucleic acid - Number of strands - From of protein coat - Enveloped or not - Shape of virus - Size

• Adenovirus - DNA - 2 - Icosahedral - Naked - Spherical - 80

• Herpesvirus - DNA - 2 - Icosahedral - Enveloped  - Roughly spherical - 100

• Picornavirus - RNA - 1 - Icosahedral - Naked - Spherical - 20 to 30

• Togavirus - RNA - 1 - Icosahedral - Enveloped - spherical - 40 to 70

• Orthomyxovirus - RNA - 1 - Helical - Enveloped - Roughly Spherical - 80 to 120

• Paramyxovirus - RNA - 1 - Helical - Enveloped - More than one form - 100 to 300

• Coronavirus - RNA - 1 - Helical - Enveloped - Roughly Spherical - 80 to 120

Note : Virus may be group into DNA or RNA viruses. Their protein coats may be Icosahedral ( a polygon with 20 faces and 13 corners), Helical or complex in symmetry. The viruses may be enveloped or without an envelope, I.e. naked.