Ebola Sudan, Ebola Zaire, Ebola Cote d'Ivoire, and Ebola Reston are the four known
strains (subtypes) of Ebola. Ebola and Marburg are the only members of the filovirus
family. Filoviruses (Ebola) are helical, non-segmented, negative, single-stranded
RNA viruses, polymorphic, noninfectious, and have variable lengths.
Infectious Ebola virions are usually 920 nm in length, 80 nm in diameter, and
have a membrane stolen from the host cell by budding. The virus encodes for a
nucleoprotein, a glycoprotein, 7 polypeptides, a polymerase, and 4 other undesignated
proteins. These proteins are made from polyadenylated mRNA transcribed in the
host cell from the virus RNA.