PROFILING FILOVIRIDAE
THE EBOLA
VIRUS
THE
MARBURG VIRUS
What's
going on with Filovirus today?
Want to know
more?
Filovirus virions are named for their
characteristic threadlike morphology (filo means "filament" in Latin).
With a lipid bilayer envelope encasing a helical nucleocapsid, they are 80
nm in
diameter and have a nucleocapsid length of 800-1000 nm.
The Filovirus genome is
a single molecule of minus sense ssRNA and is 19 kb in size. This minus
sense genome has seven open reading frames that code for the seven
known structural proteins.
Replication takes place in the
cytoplasm of host cells when the virion removes its
coat and uses its own transcriptase to transcribe its
-ssRNA into the complimentary +ssRNA. Eventually, high
concentrations of replicated viral genomes begin to
appear, marked by the formation of large inclusion
bodies with maturation occurring through budding from the plasma membrane.
The Filovirus
family was defined only through the morphologic and
replicative mechanisms of the Marburg and Ebola
viruses, compared to other -ssRNA viruses.
Filoviruses are, in fact, known only from a few
isolates in of outbreaks in Africa over the past
years -- including those of the Ebola virus in Zaire,
Sudan, and Ivory Coast, and the Marburg virus in
Zimbabwe and Kenya.

They
do not show immunological cross reactivity with each
other.
Ebola
exhibits three transcriptional start and stop codons
while Marburg has just one.
The Ebola
glycoprotein gene produces two transcripts while the
Marburg glycoprotein gene makes one.
Research groups
on the lookout for people or other primates who have
antibodies that can recognise the Marburg virus, Ebola
Zaire virus, and the Reston virus. Click on Badtz-Maru
to know more.
1995: Most
recent Ebola outbreak in Kikwit, Zaire. Click on
Pochacco to know more.
Vaccine
update: Ebola vaccine is years away. Click on Keroppi
to know more.

Created: February 1, 1999
Last modified:August 4, 1999