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Ebola Virus infection
Dr Ernet Elienguo,MDDr Chritin Nyndi,MD
EMERGENCY DEPERTMENT
ebol
outline• Background• Epidemiology• Etiology• Pathophysiology• Clinical presentation• Work up• Prognosis• Management• prevention
background• Ebola virus disease (EVD), is a severe, often fatal illness in humans.
• EVD outbreaks have a case fatality rate of up to 90%.
• EVD outbreaks occur primarily in remote villages in Central and West Africa, near tropical rainforests.
• The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.
• Fruit bats of the Pteropodidae family natural host of the Ebola virus.• • Severely ill patients require intensive supportive care. No licensed specific
treatment or vaccine is available for use in people or animals.
background
• Ebola first appeared in 1976 in 2 simultaneously outbreak in NZr Sudan and Yambuku DRC the latter in village situated near Ebola river in which the disease take it name
background
• Ebola virus is one of at least 30 known viruses capable of causing viral hemorrhagic fever syndrome
• The genus Ebolavirus is currently classified into 5 separate species: Sudan ebolavirus, Zaire ebolavirus, Tai Forest (Ivory Coast) ebolavirus, Reston ebolavirus, and Bundibugyo ebolavirus.
background
• Primary exposure• Secondary exposure
epidemiology
• Ebola and Marburg viruses are responsible for well-documented outbreaks of severe human hemorrhagic fever, with resultant case mortalities ranging from 23% for Marburg virus to 89% for Ebola virus in which more than one case occurred
epidemiology
• As of July 23, 2014, 1201 total suspected or confirmed cases (814 laboratory-confirmed) had been reported in these countries, resulting in 672 deaths
outbreak
Year Location Reported Cases, No. Deaths, No. (%)
1976 Sudan 284 151 (53)
1976 England* 1 0 (0)
1979 Sudan 34 22 (65)
2000-2001 Uganda 425 224 (53)
2004 Sudan 17 17 (41)
2011 Sudan 1 1 (100)
Total 762 405 (53)
Outbreaks
New (1) Confirmed Probable Suspect Totals
Guinea
Cases 11 362 133 11 506
Deaths 6 238 133 2 373
Liberia
Cases 45 158 306 135 599
Deaths 29 146 125 52 323
Nigeria
Cases 0 0 10 3 13
Deaths 0 0 2 0 2
Sierra Leone
Cases 13 656 37 37 730
Deaths 17 276 34 5 315
Totals
Cases 69 1176 486 186 1848
Deaths 52 660 294 59 1013
1. New cases were reported between 7 and 9 August 2014.
Disease update
• New cases and deaths attributable to EVD continue to be reported by the Ministries of Health in Guinea, Liberia, Nigeria, and Sierra Leone.
• Between 7 and 9 August 2014, 69 new cases (laboratory-confirmed, probable, and suspect cases) of EVD and 52 deaths were reported from the four countries as follows:
• Guinea, 11 new cases and 6 deaths; Liberia, 45 new cases and 29 deaths; Nigeria, 0 new cases and 0 deaths; and Sierra Leone, 13 new cases and 17 deaths.
• The current (2014) Ebola virus outbreak is significant and primarily involves 3 African countries—Guinea, Liberia, and Sierra Leone
Ep….
• Age-related demographicsIn the 1995 outbreak in Kikwit, DRC, infection
rates were significantly lower in children than in adults
Children re less likely to get into contacts. Sex-related demographicsEbola virus infection has no sexual predilectionMen more likely to get primary exposure while
oman more likely to secondary exposure
• Race-related demographicsBlackNo racil predilection
prognosis'
• The overall prognosis for patients with Ebola poor.
prognosis
• High mortality rte except for reton ebolaviru
• The most highly lethal Ebolavirus species is Zaire ebolavirus, which has been reported to have a mortality rate as high as 89%.
• Sudan ebolavirus also has high reported mortality, ranging from 41% to 65%.
clinical presentation
To type of exporePrimary exposureSecondary exposure
Clinical presentation
Clinical presentation
• Mode of tranmiionNot entirely clear but thought to firt trnmitted
to initial peron by animal body fluid or blood or by contaminated medical equipment
airbone tranmiion ha not being documented but they re however infectious breathable
Bt being identified natural reservoir
Clinical…
• Secondary exposure refers to human-to-human or primate-to-human exposures.
• In each major outbreak, medical personnel or family members who cared for patients or those who prepared deceased patients for burial were at very high risk
Clinical coure
• Incubation period range from 2 to 21 day
Clinicl coure
Severe headache (50%-74%) arthralgias or myalgias (50%-79%), fever with or without chills (95%), anorexia (45%), asthenia (85%-95%) occur early in the disease
• Gastrointestinal (GI) symptoms, abdominal pain (65%), nausea and vomiting (68%-73%) diarrhea (85%), conjunctivitis (45%), odynophagia or dysphasia (57%), bleeding from multiple sites in the GI tract.
Bleeding from mucous membranes and puncture sites is reported in 40%-50% of patients
Clinicl coure
• A mucopupular rah 15• Tackpnea i ingle mot discrimination betn
survivors n non survivors
etilogy• The known members of the family Filoviridae are the genera
Ebolavirus (Ebola virus) and Marburgvirus (Marburg virus).• Ebolavirus is classified into the following 5 separate species:
1) Sudan ebolavirus2) Zaire ebolavirus3) Tai Forest ebolavirus (formerly and perhaps still more
commonly Ivory Coast ebolavirus or Côte d’Ivoire ebolavirus)
4) Reston ebolavirus5) Bundibugyo ebolavirus
pathophyilogy
Work up
• Other diseases that should be ruled out before a diagnosis of EVD can be made include:
• malaria, typhoid fever, shigellosis, cholera, leptospirosis, plague, rickettsiosis, relapsing fever, meningitis, hepatitis and other viral hemorrhagic fever
workups
• Basic blood testsCBC(thrombocytopenia, leucopenia, and a
pronounced lymphopenia)BIOCHEMITRY(elevations in AT ALAT)CoagulopthySerum creatine and ureaSerum electrolyte
Workup
• Definitive diagnosis rests on isolation of the virus by means of tissue culture or reverse-transcription polymerase chain reaction (RT-PCR) assay.
• However, isolation of Ebola virus in tissue culture is a high-risk procedure that can be performed safely only in a few high-containment laboratories throughout the world.
Work up
Timeline of Infection Diagnostic tests availableWithin a few days after symptoms begin •Antigen-capture enzyme-linked
immunosorbent assay (ELISA) testing•IgM ELISA•Polymerase chain reaction (PCR)•Virus isolation
Later in disease course or after recovery •IgM and IgG antibodies
Retrospectively in deceased patients •Immunohistochemistry testing•PCR•Virus isolation
Work up
• Serologic testing for antibody and antigenthe immunoglobulin M (IgM) and
immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) tests may be useful in the diagnosis of Ebola virus infection
The indirect fluorescence antibody test (IFAT)IgG-capture ELISA uses detergent-extracted
viral antigens to detect IgG anti-Ebola antibodies
Work up
• Histologyendothelial cells, hepatocytes, and mononuclear phagocytesViral replication is associated with extensive
focal necrosis and is most severe in the liver, spleen, lymph nodes, kidney, lung, and gonads.
Treatments and managements
• Currently, no specific therapy is available that has demonstrated efficacy in the treatment of Ebola hemorrhagic fever.
• There are no commercially available Ebola vaccines.
• However, a recombinant human monoclonal antibody directed against the envelope GP of Ebola has been demonstrated to possess neutralizing activity
Support care
• Supportive therapy with attention tointravascular volumeElectrolytesNutritionIntravascular volume repletion is one of the
most important supportive measures.
Pharmacology agent
• To drug re currently being approved to be used
MAPPTKM-Ebola
Diet
prevention
• Work continues on a vaccine for Ebola virus infection in primates
• This work indicates that primates can be vaccinated against Ebola virus and can develop both a cell-mediated response (thought to be a result of the DNA vaccine) and a humoral antibody response (thought to be a result of the recombinant adenoviral vaccine)
prevention
• Infection control inside and outside of medical facilities relies on barrier protection using
double gloves, fluid-impermeable gowns, face shields with eye protection, coverings for legs and shoes.