U.S. hospitals or clinical laboratories concerned about a patient with potential Ebola virus exposure should contact their local and/or state public health authorities. These agencies will work with CDC to determine whether a patient is or is not a person under investigation (PUI) and whether testing is indicated. Patient status should be determined as quickly as possible in order to ensure that patient care is not compromised.
Presumptive testing for Ebola virus is available at over 50 Laboratory Response Network (LRN) laboratories located throughout the United States. Any presumptive positive Ebola test result must be confirmed at the CDC to inform public health decisions. If it is determined that testing for Ebola virus is indicated, at least 4 mL of whole blood collected in a plastic tube preserved with EDTA is the preferred sample for testing. Specimens should be shipped with refrigerant to maintain 2–8°C to the designated LRN laboratory.
For patients in the early stages of the disease, the CDC confirms EVD using the real-time polymerase chain reaction (RT-PCR) assay, but virus isolation may also be attempted. The Ebola virus can only be detected after the patient exhibits symptoms, generally reaching detectable levels within 3-10 days after the patient becomes symptomatic.
