By Abhinay Sharma Bhugoo EBOLA VIRUS

 Family Filoviridae  Genus Ebolavirus  History  First emerged in 1976  Ebola River Valley, Africa  Sub-types (well-known) 1.Zaire 2.Sudan 3.Reston 4.Tai (Ivory Coast)  Classification  Enveloped  SS negative-sense RNA  Structure  Long, filamentous, “thread-like” structure of a filovirus  “U” or “6” appearance EBOLA VIRUS BRIEF BACKGROUND

Structure-function analysis of the soluble glycoprotein, sGP, of Ebola virus – Transmembrane protein, GP(1,2) – GP gene encodes the soluble glycoproteins sGP and Delta- peptide. Genome has 7 genes: – NP, VP35, VP40, GP, VP30, VP24, and L GP1 Viral Entry GP2 Fusion and Entry Likely pH dependent EBOLA VIRUS

CURRENTLY BELIEVED ANIMAL RESERVOIR OF EBOLA VIRUS? Despite extensive studies, the natural and animal reservoir is unknown – Seems to be the rain forests on the African continent and in the Western Pacific. Non-human primates as a source of infection for humans – Carcasses of gorillas, chimpanzees and duikers during outbreaks in 2001 and 2003 – High mortality from infection in these species disqualifies them from acting as reservoirs Other considered Reservoirs – Plants, arthropods, and birds IRD researchers have identified bats as a potential natural reservoir of Ebola virus – Of 24 plant species and 19 vertebrate species experimentally immunized with Ebola virus, only bats became infected. No clinical signs were observed in these bats This is characteristic of a reservoir species

Current proposal – Bats Good vectors – If bats are among the culprits Likely to pass virus to great apes  humans May infect humans directly – Dry season More contact because of food competition Bats’ immune systems modified Virus reproduces easier In – Survey of 1,030 animals (including 679 bats) from Ebola-affected areas – Found three bat species – Viral genome fragments (RNA) in the liver and spleen – Evidence of immune response antibodies against virus in the serum CURRENTLY BELIEVED ANIMAL RESERVOIR OF EBOLA VIRUS?

Direct contact Blood, secretions, organs Unsterilized needles Burial ceremonies Documented human infections Handling of infected chimpanzees, gorillas, forest antelopes Airborne transmission limited evidence of human-human Incubation period 2 to 21 days Contagiousness Not during early stages As the illness progresses, bodily fluids represent an extreme biohazard TRANSMISSION OF EBOLA VIRUS

Initial Signs Fever (at least 102°F) Weakness & exhaustion Pain Severe headache Muscles & joints Abdominal pain Sore throat Nausea Dizziness Progressed Symptoms Vomiting Diarrhea Extensive bleeding – Red eyes hemorrhage of sclerotic arterioles – From mouth, nose, eyes, rectum & mucouse membranes Maculopapular rash – Spreads over the body (often hemorrhagic) Other secondary symptoms – Hypotension, Hypovolemia, Tachycardia – Organ damage – Internal and external bleeding SYMPTOMS OF EBOLA VIRUS

Hemorrhagic fever syndrome late symptoms: – toxic shock, hemorrhaging Direct tissue damage liver, combined with massive viremia Disseminated intravascular coagulopathy Endothelial susceptibility Subverts innate and adaptive immune responses Terminal stages – diffuse bleeding, and hypotensive shock accounts for many Ebola virus fatalities TISSUE DAMAGE LEADS TO HEMORRHAGING

Specialized laboratory test on blood specimens for detection of – Antigens – Genes of the virus – Antibodies against the virus New techniques – Non-invasive methods: saliva and urine samples Diagnosing ELISA Assay IgM ELISA PCR DIAGNOSTIC Courtesy of:

Infection Prevention – Isolation – communication – Limit direct contact – Monitor those who had lose contact with infected – Disinfect reusable equipment – Sterilize equipment Lab Safety Precautions – Education about organism – Sterile environments – Protective clothing – Proper disposal of waste products – Limit contact with contaminated medical equipment – Communication INFECTION PREVENTION AND LAB SAFETY PRECAUTIONS

One study found that guinea pigs were protected from Ebola virus infection by immunization with plasmids containing the viral genes for either the secreted or transmembrane forms of the viral glycoprotein (GP). This protection was correlated with antibody titer and antigen- specific T-cell responses to secreted GP or membrane GP. Another study found that harmless-Ebola-like particles (eVLPs) could confer immunological protection from Ebola virus infection. These eVLPs were found to be immunogenic both in vitro and in vivo. Mice were vaccinated with these eVLPs, and developed high titers of Ebola virus specific antibodies, including neutralizing antibodies. Additionally, all the mice in the study were protected from Ebola virus inoculation. CURRENT RESEARCH ON VACCINES

Biological warfare (BW) aka biological weapons, is the use of any pathogen, bacteria or virus as a weapon of war. After initial release of virus, secondary infections may occur as a result of infected individuals traveling from areas of contamination to other locations. In 1972 the Biological Weapons Convention outlawed creation and storage, but not usage, of these weapons. BIO-WARFARE

Benefits of US Aid - Russian Allies - Collaborative efforts in finding a cure for Ebola -Decreased Fear -A cut of the profits Hazards of US Aid - VECTOR removed from biowarfare threat list; however, 4 other weapons labs exist with no U.S. inspection - Difficult to verify whether former Soviet Scientists are using the American supported research for peaceful purposes - Lack of Accountability BENEFITS AND HAZARDS OF U.S AID

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