Hemorrhagic Fevers

Key Features

• Diverse group of illnesses that results from infection with one of several single-stranded RNA viruses (members of the families Arenaviridae, Bunyaviridae, Filoviridae, and Flaviviridae)

• Dengue, yellow fever, and hantaviruses are discussed separately

• The likelihood of acquiring hemorrhagic fevers among travelers is low

• Lassa fever (an Old World arenavirus)

  • Associated with rodents

  • Virus is shed in urine and droppings

  • Transmission occurs to humans either by direct contact with urine and droppings or by ingestion or inhalation of aerosolized particles

• Junin virus (cause of Argentine hemorrhagic fever) and other members of the New World Arenaviridae (Machupo virus, Sabia virus, Guanarito virus, Whitewater Arroyo virus) have similar modes of transmission

• Lujo virus is another Old World arenavirus first described in a 2008 during nosocomial outbreak

• Crimean Congo hemorrhagic fever

  • Transmitted from ticks and livestock

  • Human-to-human transmission can occur in the community or hospital setting by contact with infected body secretions

  • The geographic distribution is widespread with cases reported from Africa, Asia, the Middle East, and Eastern Europe, with increased incidence recently in the East Mediterranean region

  • Butchers and slaughterhouse workers in Southeastern Iran are at high risk for infection

  • In 2002, Turkey reported the largest outbreak with nearly 10,000 cases recorded

• Rift Valley fever

  • Transmitted by exposure to infected animal products or bite of an infected mosquito or other infected insect)

  • Risk factors include

    • Male sex

    • Working with abortive animal tissue

    • Slaughtering, skinning, or sheltering animals

    • Drinking raw milk

  • Outbreaks reported in Africa, Madagascar, and Arabian Peninsula

• Severe fever with thrombocytopenia syndrome (SFTS)

  • A new bunyavirus associated with fever and thrombocytopenia

  • Identified in 2010 in central and northeastern China

  • Differential diagnosis includes anaplasmosis, hemorrhagic fever with renal syndrome, or leptospirosis

  • A mortality of 12% was noted among the first 171 patients

  • Transmission can occur via contact with blood and possibly via aerosol

• Heartland virus

  • Similar to the SFTS virus

  • Virus appears to be amplified in deer and raccoons

  • Transmission occurs via the Lone Star tick (Amblyomma americanum)

  • Virus appears to be amplified in deer and raccoons

  • As of July 2017, more than 30 cases are reported in states in the Midwestern and southern United States

Clinical Findings

• Incubation period varies between species, ranging from 2 to 21 days

• The early phase of a viral hemorrhagic fever is indistinguishable from other viral illnesses

• Due to lack of specific symptoms on presentation, viral hemorrhagic fevers are an important cause to consider in fever of unknown origin in children in endemic areas

• The late phase is more specific and is characterized by organ failure, altered mental status, and hemorrhage

• Exanthems and mucosal lesions can occur

• In advanced stages of Lassa fever and Lujo virus infection the following can develop:

  • Significant edema

  • Pleural effusion

  • Fewer hemorrhagic manifestations compared to Ebola virus disease

  • Hearing loss in various degrees is most common complication of Lassa fever ...