WEST NILE VIRUS - HUMAN TESTING
Availability of WNV Testing
Serology testing for WNV is available at the Public Health Laboratory. The ELISA serology tests look for the presence of antibody to WNV in both serum and Cerebral Spinal Fluid (CSF). Please complete and send in the Human Specimen Test Request Form with any specimens sent for WNV testing.
Testing will be performed daily, Monday through Thursday, samples received on Fridays will be run on the following Monday as the test protocols include overnight incubations. Depending on day of submission, turn-around-time for receiving results will be approximately 2-3 workdays. For more information see our 2006 WNV Update sent to all health care providers in early May.
Quick Reference: Downloadable Forms
Human Specimen Test Request Form
Human Specimen Submission Protocol
2006 WNV Update
Ideal Timing of Specimen Collection
Timing is critical in collection of both CSF and Serum for WNV Testing. False negative test results are possible when specimens are collected too early.
· CSF specimens for IgM should be collected prior to 8 days post onset of illness.
· Acute serum specimens should be collected no earlier than 8 days post onset of illness.
· Convalescent specimens should be collected 2-3 weeks after collection of Acute serum.
Packaging and Shipping
Specimens should be transported on cold pack by overnight carrier and labeled as diagnostic specimens according to federal shipping regulations. For details on shipping and packaging of human specimens download the Human Specimen Submission Protocol.
For information on packaging and shipping of diagnostic specimens see one of the following:
US Postal Services
http://pe.usps.gov
Department of Transportation
http://hazmat.dot.gov
International Air Transportation Association
http://www.iata.org
Clinical Criteria
As a guide in determining the need for testing, it is important to reiterate the clinical criteria for West Nile Virus infection and the ideal timing of specimen collection in order to optimize testing. Patients should be evaluated by a physician for the following criteria:
- Fever greater than or equal to 38oC. (100oF), of 7-10 days duration.
- Neurologic manifestations, including; Altered mental status, altered level of consciousness, agitation, lethargy, or change in personality, headache, and/or neck pain.
- CSF pleocytosis with predominant lymphocytes and/or elevated protein,
- With or Without: Muscle weakness (especially flaccid paralysis) confirmed by neurologic exam or by EMG.
For additional information on WNV testing call the WPHL, during business hours: 307-777-7431 or Emergencies after hours: 1-888-996-9104