Ebola virus disease

Background

• An RNA based virus from the Filovirus Family with 5 species mainly originating from Africa.
• Outbreaks in Gabon, Africa occured in 1996 and in July, 2014
• Viral hemorrhagic fever
• Unknown reservoir with most likely being bats

2014 Outbreak Country Details

Countries with widespread transmission as of Dec 12, 2014

• Widespread Transmission
  • Guinea
  • Liberia
  • Sierra Leone
• Localized Transmission^
  • United States
  • Mali
• Previously Affected*
  • Nigeria
  • Senegal
  • Spain

^Persons traveling from these countries should NOT be considered to be at risk for exposure to Ebola.

2014 Domestic Outbreak Details

• September 30, 2014
  • First case diagnosed in the United States in a man who had traveled to Dallas, Texas from Liberia (Died)
• October 10, 2014
  • Healthcare worker at Texas Presbyterian Hospital who provided care for the index patient tested positive. (Recovered)
• October 15, 2014
  • A second healthcare worker who provided care for the index patient tested positive (Recovered)
• October 23, 2014
  • Medical aid worker who had returned to New York City from Guinea tested positive. (recovered)
• Current to date
  • All other 177 contacts of the index case, all people on the plane with the second healthcare worker, all contacts of the NY case, everyone else who has come from West Africa = NO CASES

Communicable Transmission

• Via blood and body fluids (urine, saliva, semen, feces, vomit) in contact with mucous membranes or via instruments such as needles

Clinical Features

• Severe, often fatal (40-65%) hemorrhagic fever
• Incubation period: 2-21 days (most commonly ~11 days)
• Patients under the age of 21 years have alower case fatality rate than those over the age of 45 years (57% vs. 94%)
• Common symptoms:
  • fever (87.1%)
  • fatigue (76.4%)
  • Loss of appetite (64.5%)
  • vomiting (67.6%)
  • diarrhea (65.6%)
  • headache (53.4%)
  • abdominal pain (44.3%)
  • Hemorrhagic symptoms (<43%)

Differential Diagnosis

Fever in traveler

• Normal causes of acute fever!
• Malaria
• Dengue
• Leptospirosis
• Typhoid fever
• Typhus
• Viral hemorrhagic fevers
  • Ebola virus disease
  • Marburg virus disease
  • Lassa fever
  • Crimean-Congo hemorrhagic fever
• Chikungunya
• Yellow fever
• Rift Valley Fever
• Q fever
• Amebiasis
• Zika virus

Evaluation

ED management algorythm

For travelers returning from countries with active Ebola follow the CDC Algorithm for Evaluation of the Returned Traveler

Persons under Investigation (PUI)

• Obtain a travel history for all persons presenting with fever
• Consider Ebola in any person who presents within 21 days of:
  • Traveling to an area with widespread transmission (see background section), OR
  • Had contact with a person who had a confirmed Ebola case

Management

Transmission Precautions

• Isolate the patient
  • single patient room (with private bathroom), door closed
• Wear appropriate PPE
  • Enhanced standard, contact, and droplet isolation precautions
  • gloves, gown (fluid resistant or impermeable), eye protection, and a facemask.
  • Additional protective equipment might be required in certain situations: double gloving, disposable shoe covers, and leg coverings
  • Have a second party monitor
• Restrict visitors
  • Avoid entry of visitors into the patient's room
  • Keep a logbook of all persons entering the patient's room
• Avoid aerosol-generating procedures
  • If necessary, use respiratory protection (N95 or higher) and perform in airborne isolation room
• Implement environmental infection control measures
  • Diligent environmental cleaning and disinfection

Contact Public Health

• Immediately report PUIs to local health authorities or CDC
  • Los Angeles repots to Acute Communicable Disease Control Program (ACDC) at 213-240-7941 (nights/weekends: 213-974-1234)
  • Special diagnostic testing requires consultation

Clinical Care

• Test and treat for other possible causes of Fever in Travelers while evaluating for Ebola
  • A few days after infectious symptoms begin, ELISA IgM, PCR or virus isolation are possible. Later in the disease or during recovery, IgM or IgG can be tested.
• CDC has guidance for safe specimen handling
  • Use point-of-care testing as much as possible
• Supportive care

Disposition

Ebola care facilities by tier

• Frontline Healthcare Facilities
  • In consultation with public health authorities:
    • Low risk: May initiate testing
    • High risk: Transfer to Ebola Assessment Hospital or Ebola Treatment Center (if locally available)
• Ebola Assessment Hospitals
  • In consultation with public health authorities:
    • Initiate initial testing
    • If confirmed case, transfer to Ebola Treatment Center
• Ebola Treatment Center
  • Admit, isolation, possible ICU for serologic results and clinical observation/supportive care.

See Also

• Fever in Travelers
• Travel Medicine
• Viral Hemorrhagic Fevers

External Links

• CDC Main Site: http://www.cdc.gov/vhf/ebola/index.html
• PPE video: http://www.medscape.com/viewarticle/833907?src=ppc_google_acq_bola_vid

References

Authors

Ross Donaldson