The Ebola virus was first discovered near the Ebola River in Congo and causes rare and deadly outbreaks in humans and nonhuman primates. It is an RNA virus that replicates inside host cells. While its natural reservoir is believed to be bats, human transmission occurs through direct contact with body fluids. Symptoms start with fever and weakness but can lead to hemorrhagic fever. Treatment involves supportive care but experimental drugs like Zmapp show promise if given early. While recovery produces antibodies, the virus can still persist in bodily fluids for months.

1. The Ebola VirusThe Ebola VirusAmina Zaman, Andrew Andrea, Sarah Harb

2. Ebola virus is named after the Ebola River in Congo where
it was first discovered.
Since then, the virus has been infecting people from time to time,
leading to outbreaks in several African countries.
History of Ebola
Scientists do not know where Ebola virus comes from.
However, based on the nature of similar viruses, they believe the virus is animal-
borne, with bats being the most likely source.

3. What is it?
Viruses do not contain enzymes for energy production or protein
synthesis.
A small infectious agent that replicates only inside the living cells of other
organisms.
A rare and deadly disease most commonly affecting people and nonhuman
primates ex. monkeys, gorillas, and chimpanzees.

4. What is it, Biologically?
Its genome encodes seven structural
proteins:
Nucleoprotein (NP)
Polymerase Cofactor (VP35), (VP40)
GP
Transcription Activator (VP30), (VP24)
RNA Ploymerase (L)
A virological taxon species.
The EBOV genome is a single-stranded RNA approximately 19,000
nucleotides long.

5. Order : Mononegavirales
Family : Filoviridae
Genus: Eblovarius
Classification
Subtypes
Ebola – Zaire
Ebola – Sudan
Ebola – Ivory Coast
Ebola – Reston
Disease in humans
Disease in non-human
primates

6. Transmission
1. Virus Reservoirs
2. Epizootic in primates
3. Primary human infection
4. Secondary Transmission

7. Transmission

8. A. Health care workers – involved in the treatment of patient with suspected or
confirmed EVD (close contact when precautions are not strictly practiced)
1. Often mistaken with early symptoms of other diseases – leading to spread with
medical centers: Malaria, Dysentery, Influenza, Typhoid fever or other bacterial
infections
2. Laboratory personnel – handling infected material
Transmission
High Risk Groups

9. B. Family and friends of infected person
1. Burial ceremonies in which mourners have direct contact with the
deceased; virus may remain up to 4 weeks after death.
2. Sexual partner of a known or suspected male case, since the
virus remains present in semen up to 3 months after recovery.
Transmission
High Risk Groups

10. Transmission
Incubation Period and Spread from Asymptomatic Infected Patients
•Incubation period: 2-21 days (Average 8-10 days)
• Early, if injected with large amount of virus by reuse of needle
• Late, if exposed with external contact to small amount of body fluid from
infected person
•When the infected person is asymptomatic (in incubation period): Non-
contagious
•When the infected person 1st start to exhibit symptoms: virus present in
blood is low, transmission is low
•When the disease progresses: High virus load in the blood, highly
contagious
•Based on Incubation Period, WHO and CDC recommend, potentially infected
people with Ebola virus – be isolated for 21 days.
 Incubation: interval between entrance
and manifestation of symptoms
Infection of Ebola virus Development of
Symptoms

11.  In women who have been infected while pregnant, the virus persists in the placenta, amniotic fluid
and fetus.
Transmission
Persistent virus in people recovering from EVD

12. Pathogenesis
“Domino Effect”
 Every tissue is affected except
for bones and muscles.
 The virus creates blood clots.
 Clots reach internal organs
(lungs, eyeball,…)
 This prevents oxygen levels to
rise in tissues resulting in
tissue death.

13. Early and Late Clinical Features
Muscle aches
Diarrhea
Fever
Increased liver
enzyme activity
Severe Headache
Vomiting
Stomach Pain Slow blood stream
Rashes
Loss of appetite
 Initial Symptoms

14. Early and Late Clinical
Features
Late Symptoms
 Diarrhea
 Coughing
 Pharyngitis
 Extreme weakness
 Severe Vomiting Blood
 Hemorrhage
 Internal and external
hemorrhages from orifices
(nose, mouth, skin, eyes)
 Low white blood cell count

15. Early and Late Clinical
Features
After symptoms develop, there is evidence of
infectivity in:
 Bodily fluids remain infectious even after death

16. Phases of illness:
1. Early (0-3 days): Fever, malaise, fatigue, body aches
2. Gastrointestinal (3-10 days):
• Primary: Gastric pain, nausea, vomiting, diarrhea
• Associated: Persistent fever, headache, chest pain, abdominal pain, hiccup
3. Shock or recovery (7-12 days):
• Shock: diminished consciousness or coma, rapid pulse, tachypnea (abnormal rapid
breathing)
• Recovery: resolution of GI symptoms, increased oral intake, increased energy
4. Late complications (≥10 days):
• Gastrointestinal hemorrhage
• Secondary infections
• Meningoencephalitis (Brain inflammation)
• Neurocognitive abnormalities
Early and Late Clinical
Features

17. •It can be difficult to clinically distinguish EVD from other infectious diseases such as
malaria, typhoid fever, meningitis and other viral hemorrhagic fevers.
•If a person had contact with the virus, he should be isolated and health professionals
notified.
•Confirmation of infection should be performed by the following methods:
Diagnosis
•The preferred specimens for diagnosis include:
1.Whole blood collected from live patients exhibiting symptoms.
2.Oral fluid specimen stored in universal transport medium collected from deceased
patients or when blood collection is not possible.

18. Treatment
• Providing IV fluids and balancing
electrolytes
• Maintaining oxygen status and blood
pressure
• Treating other infections (if they
occur)

19. Treatment
• During that epidemic, researchers were studying
an anti-Ebola drug called Zmapp.
• Doctors began using it even before the study was
complete.
• Zmapp uses antibodies discovered in mice. They
use the body’s natural immune system to fight
infection.
• If the drug is given within five days after Ebola
infection symptoms appear, it can cure the
disease.
• BUT only for Zaire

20. Recovery
• Good supportive care
• Patients immune response
• People who recover produce antibodies
lasting up to 10 years
• Long term effects such as joint and vision
problems
• Remains in semen for up to 9 months

21. Can one survive without
treatment?
• Outbreak in south Africa kills up to 60 percent of
victims
• If Ebola was never treated, it might wipe out the
population.
• Kartik Chandran says the recently discovered
human antibodies attack and destroy all five of the
viruses.
• Researchers say the antibodies work by
interfering with a process that the disease uses to
infect and multiply inside cells.

22. References
WHO VHF Pocket Book (2014)
CDC – Ebola Virus Disease
WHO – Ebola Vaccines, therapies and diagnostics
BMJ Best Practice – Ebola Virus Infection
http://www.who.int/mediacentre/factsheets/fs103/en/
http://epomedicine.com/medical-students/ebola-virus-disease/
https://learningenglish.voanews.com/a/scientists-discover-cure-for-ebola-virus/3867
https://www.cdc.gov/vhf/ebola/prevention/index.html
https://www.cdc.gov/vhf/ebola/about.html
https://www.globalresearch.ca/the-ebola-virus-pandemic-a-weapon-of-
mass-destruction/5394976