Medicine & USMLE


Viruses - RNA Viruses
  1. HIV: Microbiology and Characteristics
  2. HIV: Clinical Course
  3. Reovirus
  4. Picornavirus Overview
  5. Poliovirus
  6. Echovirus
  7. Rhinovirus
  8. Coxsackievirus
  9. Hepatitis A Virus (HAV)
  10. Hepevirus (Hepatitis E Virus)
  11. Calicivirus
  12. Flavivirus
  13. Hepatitis C Virus (HCV)
  14. Yellow Fever Virus
  15. Dengue Virus
  16. St. Louis Encephalitis and West Nile Virus
  17. Zika Virus
  18. Togavirus
  19. Rubella
  20. Retrovirus
  21. Coronavirus
  22. Orthomyxovirus
  23. Paramyxovirus
  24. Respiratory Syncytial Virus (RSV)
  25. Parainfluenza Virus (Croup)
  26. Measles
  27. Mumps
  28. Rhabdovirus
  29. Filovirus
  30. Arenavirus
  31. Bunyavirus
  32. Deltavirus


Filoviruses are a class of RNA viruses that contain single-stranded, negative-sense RNA. They utilize a helical capsid, and are further surrounded by a viral envelope. The most well-known filovirus is the ebola virus, which is a highly contagious and life-threatening virus that causes hemorrhage and DIC. Another lesser-known virus is the Marburg virus, which causes Marburg Hemorrhagic Fever. Diagnosis of filovirus infections involves a PCR to detect the viral RNA. As of now, no curative treatment for Ebola and Marburg viruses exists and most patients receive general supportive care. 

Key Points

  • Filoviruses
    • Characteristics
      • RNA viruses
        • replicate in the cytoplasm of cells
        • Single-stranded
        • - sense
        • Linear
      • Enveloped
      • Helical capsid
    • Presentation
      • Ebolaviruses
        • Transmission
          • Travel to endemic countries
            • direct contact with bodily fluids, fomites (including dead bodies), infected bats or primates (apes/monkeys)
          • high incidence of nosocomial (health-care related) infection
        • Pathogenesis
          • Targets endothelial cells, hepatocytes, phagocytes
        • Presentation
          • incubation period of up to 21 days
          • abrupt onset of flu-like symptoms (high fever, myalgia), diarrhea, and vomiting
          • DIC, diffuse hemorrhage, shock, conjunctival injection
        • Diagnosis
          • RT-PCR
            • Viral RNA detectable within 48 hrs of sxs onset
        • Treatment
          • Supportive ; no definitive treatment
            • High mortality rate
          • Strict isolation for infected individuals and barrier practices for health care workers are key in preventing transmission
      • Marburg hemorrhagic fever