Viral Hemorrhagic Fever (VHF)
2011 Case Definition

Background

New World arenaviruses include: Guanarito, Machupo, Junin, Sabia viruses.

Clinical Criteria

An illness with acute onset with ALL of the following clinical findings:

• A fever >40°C
• One or more of the following clinical findings:
  • Severe headache
  • Muscle pain
  • Erythematous maculopapular rash on the trunk with fine desquamation 3–4 days after rash onset
  • Vomiting
  • Diarrhea
  • Pharyngitis (arenavirus only)
  • Abdominal pain
  • Bleeding not related to injury
  • Retrosternal chest pain (arenavirus only)
  • Proteinuria (arenavirus only)
  • Thrombocytopenia

Laboratory Criteria for Diagnosis

One or more of the following laboratory findings:

• Detection of viral hemorrhagic fever (VHF) viral antigens in blood by enzyme-linked Immunosorbent Assay (ELISA) antigen detection
• VHF viral isolation in cell culture for blood or tissues
• Detection of VHF-specific genetic sequence by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) from blood or tissues
• Detection of VHF viral antigens in tissues by immunohistochemistry

Epidemiologic Linkage

One or more of the following exposures within the 3 weeks before onset of symptoms:

• Contact with blood or other body fluids of a patient with VHF
• Residence in—or travel to—a VHF endemic area
• Work in a laboratory that handles VHF specimens
• Work in a laboratory that handles bats, rodents, or primates from endemic areas
• Exposure to semen from a confirmed acute or convalescent case of VHF within the 10 weeks of that person's onset of symptoms

Case Classification

Comments

VHF refers to viral hemorrhagic fever caused by either Ebola, Lassa, Lujo, or Marburg virus, a New World arenavirus, or Crimean-Congo hemorrhagic fever.