II. Epidemiology
- Marburg Virus
- Outbreaks in Europe 1967, Congo 2000, Angola 2005
- Ebola Virus
- Five species with varying regions affected and mortality rates
- Outbreaks in Zaire 1976, Sudan 1970, Philipines 1989, Zaire 1995, Uganda 2000, Sudan 2004, Uganda 2007
- Ebola epidemic in West Africa (2014) in Sierra Leone, Guinea and Liberia
- By far, the largest Ebola or Marburg outbreak
- As of November 2014, West Africa: 13000 cases (nearly 8000 lab confirmed) and 4800 deaths
- A few cases have presented in Mali, Senegal, Nigeria, Spain and the U.S.
III. Pathophysiology
- Ebola Virus (Filovirus family)
- Hemorrhagic Fever viruses (associated coagulation deficits, DIC)
- Other hemorrhagic fever viruses include Lassa Fever, Yellow Fever, Dengue Fever
- Host organism
- Small animal primary reservoir is suspected (e.g. fruit bats)
- Primates appear to be as susceptible as humans to high mortality rates
- Exposure to infected primates has been responsible for many of the initial source cases in epidemics
- Spread by close contact to infected bats, primates or other humans
- Infected blood
- Body fluid
- Especially blood, stool and vomit
- Semen transmission from previously infected source has been reported
- Body tissue
- Air borne transmission is unlikely (unless aerosolized, typically during medical procedures)
IV. Precautions
- Ebola and Marburg Viruses are among the most virulent infections in humans with mortality up to 70-90%
- Initial presentation may be non-specific and mild
- Maintain vigilance and ask a careful travel history in febrile patients (e.g. endemic region, known exposures)
- Fever, severe Headache, myalgias, Vomiting, Diarrhea, Abdominal Pain, unexplained bleeding
- Immediately and completely isolate patients suspected of Viral Hemorrhagic Fever (see prevention below)
V. Course
- Incubation Period: 8-12 days (ranges from 2 to 21 days)
- Mortality is highest days 6 to 16
- Surviving patients start to improve by the second week of illness
- Virus may persist in semen and Breast Milk for a prolonged period beyond recovery
- Prolonged recovery characterized by weakness, Fatigue and persistent weight loss
VII. Findings: Manifestations
-
Influenza-Like Illness
- Abrupt onset fever, chills and malaise
- Weakness and Anorexia
- Severe Headache
- Trunk and back pain (myalgias)
- Nonproductive cough and Sore Throat
- May rapidly progress to Septic Shock and multi-organ failure
- Dermatitis
- Variably present by day 5-7 of illness
- Non-pruritic diffuse erythematous rash that may spare the legs (with or without Desquamation)
- Gastrointestinal symptoms
- Onset within a few days of initial symptoms
- Diarrhea, Vomiting and severe Abdominal Pain
- Bloody stools may occur (6% of cases)
- Bleeding
- Variably present in 20% of cases and a late manifestation
- Signs include Petechiae or Ecchymosis, mucosal bleeding or gastrointestinal Hemorrhage
- Neurologic
- Seizures, confusion and cerebral edema may occur
- Cardiopulonary
- Chest Pain, Shortness of Breath, Hiccups may occur
- Other findings
- Dark-red palatal discoloration
- Conjunctival injection
VIII. Labs
- Precautions
- CDC recommends that labs be performed on dedicated machine (e.g. iStat) not used for other patient's blood
- Logistically, labs are typically being deferred to tertiary center or department of health testing in high suspicion cases
- Complete Blood Count (CBC) with differential and Platelet Count
- Coagulation tests
- Findings consistent with Disseminated Intravascular Coagulation (DIC)
- Prothrombin (PT/INR) prolonged
- Partial Thromboplastin Time (PTT) prolonged
-
Liver Function Tests
- Serum Aspartate Aminotransferase (AST) increased (more than ALT)
- Alanine Aminotransferase (ALT) increased
- Ebola specific testing (coordinated with local health department and CDC)
IX. Management
- Supportive care in isolation suite by medical team using Full Personal Protective Equipment (see below)
- IV Fluid and Electrolyte replacement
- Supplemental Oxygen
- Vasopressors
- Mechanical Ventilation
-
Monoclonal Antibody options
- Atoltivimab/Maftivimab/Odesivimab (Inmazeb)
- Ansuvimab (Ebanga)
-
Ribavirin (Virazole)
- See Viral Hemorrhagic Fever for protocol
X. Prognosis
XI. Prevention
- Complete patient isolation
- Isolated room with designated bathroom or commode
- Designated care team in full PPE minimize broader exposures
- Full Personal Protective Equipment (PPE) for healthcare workers (donning and doffing)
- Vacinnation
- Ebola Zaire Vaccine (age over 18 years)
- Single dose 1 ml IM for preexposure, or immediate postexposure
- Ebola Zaire Vaccine (age over 18 years)
XII. Resources
XIII. References
- Black, Martin, DeVos (2018) Crit Dec Emerg Med 32(8): 3-12
- Bray in Hirsch (2014) Ebola and Marburg Virus Disease, UpToDate, accessed online 11/5/2014
- Nordurft-Froman and DeVos (2022) Crit Dec Emerg Med 36(4): 4-15
- (1995) MMWR Morb Mortal Wkly Rep 44:381-2 [PubMed]