Ebola VirusEbola Virus

Hemorrhagic Fever

OutbreaksOutbreaks

1976- First Major Outbreak (ZEBOV)

1976- Sudan (SEBOV)

Occur Sporadically www.cdc.gov for

more information

Where does Ebola hide?Where does Ebola hide? 2002- Fruit Bats Antibodies against Ebola Ebola Gene sequences in

liver and spleen Fruit bats do not show any

symptoms Best candidate to be the

reservoir More research needs to be

done

GeographyGeography The link between human infection by the Ebola virus and

their proximity to primates is clear. -Outbreaks occurred in countries that house 80 percent of

the world’s remaining wild gorilla and chimpanzee populations.

- The outbreaks coincided with the outbreaks in wild animals.

- The same distinct viral strains were isolated in animal carcasses and in the bodies of those who handled those carcasses.

- These outbreaks were preceded by an abnormally large death in wild Gorilla populations.

Clinical Observations Clinical Observations Incubation period: 2-21 days

Stage I (unspecific): -Extreme asthenia (body weakness) -diarrhea, nausea and vomiting, anorexia abdominal pain - headaches - arthralgia (neuralgic pain in joints) - myalgia (muscular pain or tenderness), back pain - mucosal redness of the oral cavity, dysphagia (difficulty in

swallowing) - conjunctivitis. - rash all over body except in face

** If the patients don’t recover gradually at this point, there is a high probability that the disease will progress to the second phase, resulting in complications which eventually lead to death (Mupapa et al., 1999).

Stage II (Specific): - Hemorrhage - neuropsychiatric abnormalities - anuria (the absence of urine formation) - hiccups - tachypnea (rapid breathing).

** Patients who progressed to phase two EHF almost always die. (Ndambi et al., 1999)

Late Complications: -Arthralgia - ocular diseases (ocular pain, photophobia and hyperlacrimation) - hearing loss - unilateral orchitis( inflammation of one or both of the testes) ** These conditions are usually relieved with the treatment of 1%

atropine and steroids

EpidemiologyEpidemiology  Ebola Hemorrhagic Fever was first found in 1976 It struck two countries within that year a.  Sudan – in a town called N’zara b.  Zaire, now known as the Democratic Republic of

Congo   In these two instances the mortality rate was between 50 –90% Following those epidemics, Ebola hit Africa in many other

instances the worst yet being in the year 2000 when it struck Uganda infecting more than 400 people.

TransmissionTransmission

contracted through contact of any infected individual’s body fluids

Ebola HF prevention poster used in Kikwit outbreak.

Controlling the spread of Ebola Controlling the spread of Ebola a. Hospitals must follow precautionary methods, such as:  1.      wearing gloves 2.      isolating infected individuals 3.      practicing nurse barrier techniques 4.      proper sterilization and disposal of all equipment b.  Burials must be done correctly 1.      no washing or touching carcass 2.      put into body bags and bury outside city c. Report any questionable illness to officials                   

Ebola SubtypesEbola Subtypes

Ebola-Zaire (ZEBOV)

Ebola-Sudan (SEBOV)

Ebola Ivory-Coast (ICEBOV)

Ebola-Reston (REBOV)

MOLECULAR STRUCTUREMOLECULAR STRUCTURE Characterization of the virus

– Order: Mononegavirales– Family: Filoviridae– Genus: Ebolavirus– Species: Ebola-Zaire, Ebola-Sudan, Ebola-Cote d-Ivoire, Ebola-Reston

Morphology under electron microscope– filamentous, enveloped RNA virus– approx. 19 kb in length (1 kb = 1000 RNA bases/nucleotides) or 60-80 nm in diameter– single-stranded, linear, non-segmented– negative-sense RNA (encoded in a 3’ to 5’ direction)– appears to have “spikes” due to glycoprotein on outside membrane

Structure of Ebola genome and proteins– Transcribed into 8 sub-genomic mRNA proteins: 7

structural and 1 nonstructural– 7 structural proteins:

– nucleoprotein (NP)– 4 viral/virion proteins (VP35, VP40, VP30, VP24)– glycoprotein (GP)– RNA-dependent RNA polymerase (L protein)

• NP, VP35, VP30, L protein: required for transcription & replication

• VP40, GP, VP24: associated with the membrane

Proteins Proteins

EthicsEthics Biogeograophical Ethics is defined as motivation

based on ideas of right and wrong when dealing with the geographical distribution of animals and plants.

This concept of can be used to explain the world’s shockingly small response to the Ebola Virus.

Because there was little travel to that region by people of more developed countries, there was not much economic drive for a vaccine, treatment, and aid in prevention.

BioterrorismBioterrorism

Since the September 11 bombings in the United States, the locality of this virus has become less isolated as the threat of bioterrorism looms large.

The Ebola virus is now on the “A” list for hopeful vaccination development.

Experiments have even been formed to show how Ebola can be used as a bioterror agent.