Clinical Screening and Diagnosis for VHFs

Key points

  • Viral hemorrhagic fevers (VHFs) are rare and deadly viral illness that are reportable in all U.S. states and territories.
  • Be alert for and evaluate any patients that are suspected of having a VHF.
  • If you suspect a VHF after screening, isolate the patient and notify your health department.

VHF Case Definitions

Suspect case

  1. Signs and symptoms compatible with a VHF

AND

  1. An epidemiological risk factor within 21 days (i.e., the incubation period) before the onset of symptoms.

Confirmed case

Laboratory-confirmed diagnostic evidence of a VHF (i.e., through molecular and/or serologic testing).

Screening guidelines

The majority of febrile patients presenting in U.S. healthcare facilities do not have a VHF, but early symptoms are similar to other febrile illnesses. It is important to systematically assess patients for the possibility of a VHF through a triage and evaluation process.

Identify potential exposures

Getting a thorough history is important for all patients exhibiting symptoms compatible with a VHF who may have had an exposure to the virus.

Important questions to ask to begin assessing exposure risk:

  • Have you been in contact with a person with suspect or confirmed VHF in the past 21 days (for example touching, caring for, etc.)?
  • Have you been to an area with an active VHF outbreak or where VHF is endemic in the past 21 days? Stay up to date on active .

Ask about VHF risk factors

Exposure risks for VHFs may include the following activities.

  • Contact with a symptomatic person with a suspected or confirmed VHF, or any objects contaminated by their body fluids
  • Experienced a breach in infection prevention and control precautions that result in the potential for contact with body fluids of a patient with a suspected or confirmed VHF
  • Contact with semen from a person who has recovered from a VHF
  • Participated in any of the following activities while in an area with an active VHF outbreak or where VHFs are endemic:
    • Having contact with someone who was sick or died, or any objects contaminated by their body fluids
    • Attending/participating in funeral rituals, including preparing bodies for funeral or burial
    • Working in a healthcare facility or laboratory
    • Visiting a healthcare facility or traditional healer
    • Having contact with bats or wild animals
    • Working or spending time in a mine/cave

Ask about signs or symptoms compatible with a VHF

Signs and symptoms of most VHFs are nonspecific and similar to many other common causes of febrile illness in returning travelers. Assess a patient's signs and symptoms along with their travel history and epidemiologic risk factors before initiating immediate infection control measures.

VHF symptoms can appear anywhere from 2 to 21 days after exposure to the virus.

Illness typically progresses from "dry" symptoms (fever, aches, fatigue) to "wet" symptoms (diarrhea, vomiting, and in some cases, bleeding). A person with a VHF is not contagious until the appearance of symptoms.

Primary signs and symptoms of VHFs often include some or several of the following:

  • Fever (≥100.4°F/38.0°C)
  • Aches and pains, such as severe headache and muscle and/or joint pain
  • Weakness and fatigue
  • Sore throat
  • Loss of appetite
  • Gastrointestinal symptoms including abdominal pain, diarrhea, and vomiting
  • Unexplained hemorrhaging, bleeding or bruising
  • Red eyes, skin rash, and hiccups

What to do next

If Patient Evaluation Indicates Possible Infection with a VHF, Take Action

Isolate

  • Isolate the patient in a single room with a private bathroom or a covered bedside commode.
  • Adhere to infection prevention and control procedures to prevent transmission through direct or indirect contact, including wearing appropriate PPE and using dedicated equipment.
  • Use only essential healthcare workers trained in their designated roles for patient care and keep a log of everyone who enters and leaves the patient's room.
  • Perform only necessary tests and procedures and avoid aerosol-generating procedures.

Inform

  • Notify your facility's Infection Prevention and Control Program and other healthcare personnel of a suspect VHF case.
  • Contact the local or state health department for consultation about VHF testing.

If the patient is not reporting signs and symptoms compatible with a VHF but concern remains, consult Local/State Health Department for additional guidance on testing recommendations.

Resources

  • Borio L, Inglesby T, Peters CJ, et al: . JAMA 287: 2391–2405, 2002.
  • Hsu CH, Champaloux S, Keïta S, et al. . Emerg Infect Dis. 2018 Jan; 24(1): 9–14.