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.