Ebola Virus Hemorrhagic Fever Outbreaks 1976 First Major

Ebola Virus Hemorrhagic Fever

Outbreaks 1976 - First Major Outbreak (ZEBOV) l 1976 - Sudan (SEBOV) l Occur Sporadically l www. cdc. gov for more information l

Where does Ebola hide? l l l 2002 - Fruit Bats Antibodies against 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

Geography l 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 l Incubation period: 2 -21 days l 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).

l 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) l 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

Epidemiology 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% l 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. l l l

Transmission l contracted through contact of any infected individual’s body fluids Ebola HF prevention poster used in Kikwit outbreak.

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 l b. Burials must be done correctly 1. no washing or touching carcass 2. put into body bags and bury outside city l c. Report any questionable illness to officials l

Ebola Subtypes Ebola-Zaire (ZEBOV) l Ebola-Sudan (SEBOV) l Ebola Ivory-Coast (ICEBOV) l Ebola-Reston (REBOV) l

MOLECULAR STRUCTURE l Characterization of the virus – – l 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

l Structure of Ebola genome and proteins – Transcribed into 8 sub-genomic m. RNA proteins: 7 structural and 1 nonstructural – 7 structural proteins: – – nucleoprotein (NP) 4 viral/virion proteins (VP 35, VP 40, VP 30, VP 24) glycoprotein (GP) RNA-dependent RNA polymerase (L protein) • NP, VP 35, VP 30, L protein: required for transcription & replication • VP 40, GP, VP 24: associated with the membrane

Proteins

Ethics Biogeograophical Ethics is defined as motivation based on ideas of right and wrong when dealing with the geographical distribution of animals and plants. l This concept of can be used to explain the world’s shockingly small response to the Ebola Virus. l 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. l

Bioterrorism 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. l The Ebola virus is now on the “A” list for hopeful vaccination development. l Experiments have even been formed to show Ebola can be used as a bioterror agent. l