Presented By Dr.N.Sudarmani Gayathri Department of Biochemistry Sree Narayana Guru College-Coimbatore

1. EBOLA
VIRUSES
Presented By
Dr. N.Sudarmani Gayathri
Asst.Prof
Dept. of Biochemistry

2.  Ebola is a viral hemorrhagic (bleeding) illness that has a high fatality rate.
 It was discovered in 1976 near the Ebola River in the present-day Democratic Republic of
Congo
 Ebola virus: Family :Filoviridae
Genera(Three): Cuevavirus, Marburgvirus, and Ebolavirus
Order :Mononegavirales.
 Five species of Ebola virus have been identified: Zaire, Sudan, Bundibugyo, Reston, and Taï
Forest.
 Bundibugyo ebolavirus, Zaire ebolavirus, and Sudan ebolavirus have been associated with
large outbreaks in Africa.
 Four of the strains (Reston is the exception) are responsible for outbreaks in humans
 Once the virus spreads to a human, person-to-person transmission is possible.
 Humans can contract the virus by coming into close contact with the body or bodily fluids
(including blood) of an infected animal.
 The West African outbreak was caused by Zaire ebolavirus, which is also the most virulent
among the five species.
 Since 1976 it has caused multiple outbreaks in Central Africa, with a mortality rate of 55%–
88%.
 The Ebola virus genome contains a single strand of non segmented, negative-sense viral
genomic RNA

4. The incubation period is 2 - 21 days.
• Human are not infectious until they develop symptoms.
• Initial symptoms are sudden onset of fever and fatigue, muscle pain, headache and sore throat.
• Usually followed by: anorexia, nausea,vomiting, diarrhoea, rash, impaired kidney and liver,
abdominal pain, cough, shortness of breath, postural hypotension, edema, headache, confusion,
and coma.
In some cases, a maculopapular rash develops after 5–7 days of symptoms.
Spontaneous bleeding internally and externally (such as mucosal hemorrhages, nose bleeding,
vomiting/coughing up blood, blood in stool, petechiae, ecchymoses, uncontrollable bleeding
from venipuncture sites).
These complications are the most common causes of death in patients.
Gastrointestinal symptoms are the most common in the current outbreak(2014-2015)
CLINICAL FEATURES OF EBOLA VIRUS

5. Definitive diagnosis requires testing:
• Reverse transcriptase polymerase chain reaction (RT-PCR)
assay
• IgGand IgM antibodies with enzyme-linked immunosorbent
assay (Elisa)
• Antigen detection tests
• Serum neutralization test
• Virus isolation by cell culture
• Electron microscopy

6. • Therapeutic monoclonal antibodies isolated from human volunteers
vaccinated with recombinant adenovirus expressing Ebola virus
glycoprotein (EBOV GP) and boosted with modified Vaccinia virus Ankara.
• Among 82 antibodies isolated from peripheral blood B cells, almost half
neutralized GP pseudo typed influenza virus.
• The antibody response was diverse in gene usage and epitope recognition.
• Although close to germline in sequence, neutralizing
antibodies with binding affinities in the nano- to pico-molar range, similar
to “affinity matured” antibodies from convalescent donors, were found.
• They recognized the mucin-like domain, glycan cap, receptor binding
region, and the base of the glycoprotein.
• A cross-reactive cocktail of four antibodies, targeting the latter three non-
overlapping epitopes, given on day 3 of EBOV infection, completely
protected guinea pigs.
• This study highlights the value of experimental vaccine trials as a rich
source of therapeutic human monoclonal antibodies.
https://www.sciencedirect.com/science/article/pii/S2211124719303274

7. EVD Treatment
• Rehydration with oral or intravenous fluids - and treatment of specific
symptoms improves survival.
• There is as yet no proven treatment available for EVD.
• A range of potential treatments including blood products, immune
therapies and drug therapies are currently being evaluated.
VACCINES
• An experimental Ebola vaccine proved highly protective against EVD in
a major trial in Guinea in 2015.
• The vaccine, called rVSV-ZEBOV, was studied in a trial involving 11 841
people.
• Among the 5837 people who received the vaccine, no Ebola cases were
recorded 10 days or more after vaccination. In comparison, there were
23 cases 10 days or more after vaccination among those who did not
receive the vaccine.
• The rVSV-ZEBOV vaccine is being used in the ongoing 2018-2019 Ebola
outbreak in DRC.
• Pregnant and breastfeeding women should have access to the vaccine
under the same conditions as for the general population.
TREATMENT OF EBOLA VIRUS
Structure of EBOLA virus using
TEM

8. PRECAUTIONS
Reducing the risk of wildlife-to-human transmission:
 Avoid contact with infected fruit bats or monkeys/apes and the consumption of
their raw meat.
 Animals should be handled with gloves and other appropriate protective clothing.
 Animal products (blood and meat) should be thoroughly cooked before
consumption.
Reducing the risk of human-to-human transmission
 Avoid from direct or close contact with people with Ebola symptoms, particularly
with their bodily fluids.
 Gloves and appropriate personal protective equipment should be worn when taking
care of ill patients at home.
 Regular hand washing is required after visiting patients in hospital, as well as after
taking care of patients at home.
 Organize safe and dignified burials for people who may have died of Ebola Virus
Disease