Ebola

By Elyas Shaiwani

Family

M a rb u rg

Z a ire S ud an Ivo ry C o a st R e s ton

E b o la

F ilo v id irae

Reservoir/Host

• Suspected Reservoirs– Bats

– Rats

– Insect

– Birds

• Hosts– Humans

• Except EBO-R

– Non-human primates

Types of Transmission

• Exchange of body fluids– Saliva, semen, vaginal

secretion, vomit, blood, etc

– Improper needle use

– Viral exposure to ocular, nasal and oral regions

Structure• 7 genes for 8 proteins

– GP and sGP• GP - adheres to endothelial cells

and macrophages

• sGP - binds to macrophages to prevent cytokine release and kills host cell during reproduction

– VP24 • May help in uncoating during

infection

– VP30• Binds RNA to DNA

– VP35• Key in replication within host

cell

– VP40 • Responsible for budding at

the plasma membrane

– NP• Protein envelope

– Polymerase (L)• Unknown function

Mechanism• GP attaches virus to endothelial

cell

• VP24 allow viral contents to enter cell

• VP35 and RNA begin synthesis and translation

• High virus concentration and sGP concentration interfere with cell function and eventually lyse the host cell

• sGP released inhibits macrophage and neutrophil cytokine release thus stopping inflammation

Symptoms

• Ebola Hemorrhagic Fever– 2 - 21 days incubation– Week 1

• Headache, malaise, abdominal pain, fatigue, fever, bloody diarrhea, bloody vomit, conjunctivitis, nausea

• Mild anorexia, irritablity

– After 1st week• Shock, dry heaves with

possible black bile, internal bleeding or externally from orifices, limited or loss of liver and kidney functions, death

• Memory loss, confusion, anxiety, anorexia

– 90% mortality rate

Treatment

• Supportive care– Blood transfusions

– Antibodies

• Preventative Measures– Quarantine

• Individual and towns

– Reverse quarantine

– Aseptic technique

– BSL4 precautions

References

• http://www.africaphotos.com/stock/subject/health/ebola/cz10a.htm

• http://www.rki.de/INFEKT/Ebola/Frame.htm

• http://www.stanford.edu/group/virus/filo/class.html

• Formenty et al. “Human Infection Due to Ebola Virus, Subtype Cote d’Ivoire: Clinical and Biological Presentation.” The Journal of Infectious Diseases 1999;179.

• “HHMI News: Ebola’s Deadly Secrets.” Howard Hughes Medical Institute. http://www.hhmi.org/news/nabel.html

• “Ebola and lassa viruses taret dendritic cells and prevent cytokine release.” Medical Letter on the CDC and FDA. May 4 2003. http://www.newsrx.com