Laboratory Testing for Patients with a Suspected VHF or High-Consequence Disease

What to know

  • Healthcare providers who suspect a patient is ill with a viral hemorrhagic fever (VHF) or other high-consequence disease must conduct an initial screening, isolate the patient, and notify their health department before testing can take place.
  • Routine laboratory testing to monitor the patient’s clinical status and diagnostic testing for other potential causes of the patient’s illness should be pursued while testing for a VHF or other high-consequence disease is underway.


Cases of VHFs or other high-consequence diseases in the United States are rare. Most ill travelers returning from an active VHF or other high-consequence disease outbreak or endemic area who undergo testing do not have a VHF or other high-consequence disease. They are typically diagnosed with a more common etiologic agent, like malaria. Timely identification of other more likely pathogens and access to routine laboratory testing, such as blood counts and chemistries, is essential for providing appropriate patient care.

Clinical laboratories can safely perform common diagnostic testing by following Standard Precautions for All Patient Care which includes the Bloodborne Pathogen Standard (29 CFR 1910.1030).

Early consideration of a VHF or other high-consequence disease in the differential diagnosis of a patient with applicable clinical and epidemiological factors is essential for providing appropriate care and preventing the spread of infection. It is important to systematically assess patients through a screening process.

Clinicians with concerns about a VHF or other high-consequence virus infection during the differential diagnosis of their patient's illness should contact their jurisdictional health department immediately (via the 24-hour Epi-On-Call contact list) and follow jurisdictional protocols. Clinical teams should coordinate with public health officials and CDC to assess the risk of a VHF or other high-consequence disease based on the clinical presentation and epidemiologic risk factors to determine if VHF or other high-consequence disease testing is needed, and what other causes of illness should be considered (e.g., malaria).

This coordination can ensure proper patient care and appropriate precautions are taken to help prevent potential spread. In the hospital setting, where policies and procedures should be in place to safeguard health care workers, consideration of a VHF or other high-consequence disease should not delay diagnostic assessments, laboratory testing, and appropriate care for other, more likely medical conditions.

CDC's Viral Special Pathogens Branch (VSPB) is available 24/7 for consultations on VHFs or other HCID by calling the CDC Emergency Operations Center at 770-488-7100 and requesting VSPB's on-call epidemiologist.

Testing guidance