Yemeni International Congress of Infectious Diseases

16-18 December 2014 University of Science & Technology Hospital

Faculty of Medicine & Health Sciences

Ebola Virus Disease(EVD)

Presented by:

Dr Ahmed Ali Qaid Pandemic and Epidemic Disease Officer,WHO

Professor of Community Medicine

Dr Abdullah Abdu Almikhlafy

Assistant Professor of Community Medicine

UST FOM

Ebola The Deadly African

Virus

Ebola Virus Introduction

First appeared in Africa 1976

“African Hemorrhagic Fever”

acute,mostly fatal disease

causes blood vessel “bursting”

systemic (all organs/tissues)

humans and nonhuman primates

Excluding „2000 outbreak

1,500 cases

over 1,000 deaths

Ebola Taxonomy

Scientific Classification

Order: Mononegavirales

Family: Filoviridae

Genus: Ebola like viruses

Species: Ebola

Subtypes

Ebola-Zaire, Ebola-Sudan,Ebola-Ivory Coast

disease in humans

Ebola-Reston disease in nonhuman primates

Learning Objectives

To Recognize the Epidemiological Pattern of Ebola Virus Disease .

To Understand Prevention and Control Methods for Ebola Virus Disease.

Filoviridae or “Filoviruses”

Most mysterious virus group

Pathogenesis poorly understood

Ebola

natural history/reservoirs unknown

exist throughout the world

endemic to Africa Image courtesy of the Centers for Disease Control

Ebola Pathogenesis

Enters Bloodstream

skin, membranes,open wounds

Cell Level

docks with cell membrane

Viral RNA

released into cytoplasm

production new viral proteins/ genetic material

New viral genomes

rapidly coated in protein

create cores

Copyright: Russell Kightley Media, Australia

Ebola Virus Zoonotic virus – bats the most likely reservoir, although

species unknown

Spillover event from infected wild animals (e.g., fruit bats, monkey, duiker) to humans, followed by human-human

transmission

9

Ebola Epidemiology

Reservoirs in Nature largely unknown

possibly infected animals (primates?)

Transmission

direct contact blood/secretions of infected person

possible airborne (Reston primate facility)

Onset of illness abrupt

incubation period: 2 to 21 days

infections are acute and mostly deadly

EVD in West Africa up to Epi-Week 45

Source: (i) World Health Organization, (ii) WHO Ebola Response Team: the first 9 months of epidemic and forward projection. N Eng J Med, 2014 Sep 22 {Epub ahead of print]

History of EVD Outbreaks (1)

● In 1976, Ebola Virus Disease (EVD) (formerly known

as Ebola Haemorrhagic Fever) was first appeared in 2

simultaneous outbreaks in Sudan and in Democratic

Republic of Congo (DRC).

● Twenty three outbreaks (2388 human cases including

1590 deaths, CFR 67%) have been reported since the

first discovery of EVD in 1976 and up to 2013.

Uganda, 2000 (425)

Côte d’Ivoire 1994 (1)

Gabon, 1994 (44)

1996 (37), 1996 (61) 2001-02 (65)

Sudan, 1976 (284), 1979 (34)

DRC (ex-Zaire), 1976 (318) 1977 (1) 1995 (316)

South Africa 1996 (1)

Congo, 2001-02 (57) 2002 (13) 2003 (143) (35)

Ebola haemorrhagic fevers in Africa

Epidemics

Countries with serological evidence

(n) = number of cases

Countries at risk

Countries w/o serological evidence

EVD: Current Situation in EMR

● Rumours of EVD have been reported from Egypt,

Lebanon, Morocco, KSA, Sudan and UAE.

● Sudan remains the only country in the region that

has experienced previous outbreaks from EVD

● The risk of the spread of EVD to the region region is

possible owing to international travel

Possible EVD importation Route (1)

● International travel by air

─ Traders and businessmen from affected countries in West Africa

─ Transit passengers

─ Returnee UN Peacekeepers from Western Africa

─ Religious pilgrims.

Potential of spreading internationally by air travel:

These were the final destinations of airline travelers in the month of August-September 2014 departing from the affected countries by WHO Region…

Source: Assessing the international spreading risk associated with 2014 Western African Ebola Outbreak. PLOS Current Outbreaks, 2014 Sep2 Edition 1

Possible EVD importation Route (2)

● International travel by land and/or sea

─ Illegal economic migrants to Europe

─ Pilgrims from West Africa

─ Job seekers and seasonal workers

Transmission mode

How contagious is EVD? ?

●H2H Transmission : familial and nosocomial

•Most human infections due to direct or indirect contact with damaged skin, mucous membranes, body fluids of infected patients (blood, saliva, vomitus, urine, stool, semen)

●Amplification : 584 HCWs infected in the

current outbreak of which 329 have died

•Hospital: health care workers, in-patients,

care givers, unsafe injections

•Community: contacts when caring for ill,

funeral

Symptoms and Diagnostic Tests

Early symptoms

muscle aches, fever, vomiting

red eyes, skin rash, diarrhea, stomach pain

Acute symptoms

bleeding/hemorrhaging from skin, orifices, internal organs

Early Diagnosis

very difficult

signs & symptoms very similar to other infections

Laboratory Test PCR detection

ELISA (enzyme-linked immuno-absorbant) assay

Treatment

No Standard Treatment available

Patients receive supportive therapy

treating complicating infections

balancing patient‟s fluids and electrolytes

maintaining oxygen status and blood pressure

Clinical Features

Incubation period 2 to 21 days (3-‐12).

 Sudden onset of fever, weakness, muscle pain,

headache and sore throat, conjunctivitis, hiccups,

dysphagia.

 followed by vomiting, diarrhea, rash.

 internal & external bleeding

often absent or minimal

Late features

Confusion and irritability

 Seizures

 easy bleeding;

– Rash e.g. ecchymosis, petechiae, purpura

– bleeding from the gums,

– conjunctival hemorrhage

– oozing from puncture sites

Late features

 --epistaxis – Hematemesis – hemoptysis – Melaena -unexplained vaginal bleeding in women – haematuria  Fever may be absent in late stages Shock (compounded by dehydration)

Classification Criteria

Suspected

Any person, alive or dead, who has (or had) sudden onset of high fever and had contact with a suspected, probable or confirmed EVD case, or a dead or sick animal OR any person with sudden onset of high fever and at least three of the following symptoms: headache, vomiting, anorexia/ loss of appetite, diarrhoea, lethargy, stomach pain, aching muscles or joints, difficulty swallowing, breathing difficulties, or hiccup; or any person with unexplained bleeding OR any sudden, unexplained death.

Probable

Any suspected case evaluated by a clinician OR any person who died from ‘suspected’ EVD and had an epidemiological link to a confirmed case but was not tested and did not have laboratory confirmation of the disease.

Confirmed

A probable or suspected case is classified as confirmed when a sample from that person tests positive for EVD in the laboratory.

Table 3: Ebola case-classification criteria

WHO aims to prevent Ebola outbreaks by

maintaining surveillance for Ebola virus disease and supporting at-risk countries to developed preparedness plans. The document provides

overall guidance for control of Ebola and Marburg virus

outbreaks: Ebola and Marburg virus disease epidemics: preparedness, alert, control, and

evaluation

WHO response

When an outbreak is detected WHO responds by supporting surveillance, community engagement, case management, laboratory services, contact tracing, infection control, logistical support and training and assistance with safe burial practices. WHO has developed detailed advice on Ebola infection prevention and control: Infection prevention and control guidance for care of patients with suspected or confirmed Filovirus haemorrhagic fever in health-care settings, with focus on Ebola

WHO response

WHO Ebola Response- Overview

The first case of the current Ebola Virus Disease (EVD) was reported in Guinea in March 2014. Since then the outbreak has spread to Sierra Leone, Liberia, Nigeria and Senegal.

A separate Ebola outbreak in the Democratic Republic of Congo was also reported in August 2014.

8 countries affected – High transmission: Guinea, Liberia, Sierra Leone – Recently introduced / low transmission: Mali, Spain, US – Ebola free: Nigeria, Senegal

Prevention

No vaccines!

Patients are isolated

Medical Staff Training western sanitation practices

intake

care during stay

after patient dies

Infection-control Measures complete equipment and area sterilization

Prevention

After Death

Virus contagious in fluids for days

Burial use extreme caution

handling and transport

cultural practices/ religious belief

incinerate all waste !!!!

INFECTION PREVENTION

Consider every person (client or staff)

infectious

Wash hands

 Wear gloves

 Use physical barriers:

(protective goggles

facemasks and aprons)

To Prevent Ebola The suspected reservoirs for Ebola are fruit

bats.

Transmission to humans is thought to originate from infected bats or primates that have become infected by bats.

Undercooked infected bat and primate (bush) meat transmits the virus to humans.

 

To Prevent Ebola

Human to human transmission is only achieved by physical contact with a person who is acutely and gravely ill from the Ebola virus or their body fluids

Transmission among humans is almost exclusively among caregiver family members or health care workers tending to the very ill.

 The virus is easily killed by contact with soap, bleach, sunlight, or drying. A washing machine will kill the virus in clothing saturated with infected body fluids.

To Prevent Ebola

 A person can incubate the virus without symptoms for 2‐21 days, the average being five to eight days before becoming ill. THEY ARE NOT CONTAGIOUS until they are acutely ill.

Only when ill, does the viral load express itself first in the blood and then in other bodily fluids (to include vomit, feces, urine, breast milk, semen and sweat).

If you are walking around you are not infecious to others..   As always practice good hand washing techniques. You will not contract Ebola if you do not touch a dying person with it.

Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a severe, often fatal illness in humans.

The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.

The average EVD case fatality rate is around 50%. Case fatality rates have varied from 25% to 90% in past outbreaks.

Take-home messages

Community engagement is key to successfully controlling outbreaks. Good outbreak control relies on applying a package of interventions, namely case management, surveillance and contact tracing, a good laboratory service, safe burials and social mobilisation.

Take-home messages

Early supportive care with rehydration, symptomatic treatment improves survival. There is as yet no licensed treatment proven to neutralise the virus but a range of blood, immunological and drug therapies are under development.

There are currently no licensed Ebola vaccines but 2 potential candidates are undergoing evaluation.

Take-home messages

Thank You For your Attention And Listening