West Nile Virus, RNA, PCR, Molecular Detection, Spinal Fluid
Use
The test is used for rapid detection of West Nile virus (WNV) RNA in cerebrospinal fluid (CSF) specimens. It is particularly useful as an adjunctive test to serology for the detection of early WNV infection, especially during the first few days after symptom onset. The test is not intended for screening asymptomatic individuals and should only be used for testing patients with clinical signs and symptoms indicative of WNV disease.
Special Instructions
This test should be complemented by serological tests for a comprehensive diagnosis due to the potential for cross-reactivity with other flaviviruses in serological tests. Collection instructions emphasize not to centrifuge or heat inactivate the sample. For accurate diagnosis, results should be interpreted alongside clinical findings and serologic test outcomes.
Limitations
The assay's sensitivity is highly dependent on the timing of specimen collection relative to illness onset. A negative result does not rule out WNV infection. The test detects both viable and nonviable virus, and the viral load in the specimen might not correlate with cell culture results. PCR is most effective within a few days post-symptom onset, but precision may vary across different specimen types.
Methodology
PCR-based (RT-PCR)
Biomarkers
LOINC Codes
- 34461-4
- 34461-4
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
0.5 mL
Minimum Volume
0.3 mL
Container
Sterile screw cap vial
Collection Instructions
Preferred vial number is 2; any vial number is acceptable. Do not centrifuge or heat inactivate.
Storage Instructions
Refrigerate or freeze. Stability of 7 days for both refrigerated and frozen.
Causes for Rejection
Heat-inactivated specimen
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 7 days |
| Frozen | 7 days |
