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Arbovirus Antibody Panel, CSF (IgM)

Viral Encephalitis, West Nile Virus (WNV), California Group Virus (CGV), St. Louis Encephalitis (SLE), Eastern Equine Encephalitis (EEE), CSF Arbovirus Antibody Panel, IgM

Test Codes

EPIC: LAB6490, Beaker: XAVMC, MDHHS

Department

Send Outs

Instructions

Arboviruses are transmitted to humans by hematophagous arthropods (i.e., mosquitoes and ticks), therefore, testing is only available in warm months when transmission is probable. Specimens collected November-April will be sent to ARUP Laboratories by special request only.

Specimen Collection Criteria

Collect: 2.0 mL Cerebrospinal fluid (CSF) in a sterile collection container. (Minimum: 1.5 mL)

The following information must be provided:

1. Date of onset of disease
2. Travel history
3. Vaccine history (e.g., Yellow Fever vaccination, Japanese Encephalitis virus vaccination, etc.)
4. Date of collection
5. Clinical symptoms that suggest encephalitis
6. Patient's home address

Physician Office/Draw Specimen Preparation

Transfer CSF into a skirted capped, plastic vial and maintained refrigerated (2-8°C or 36-46°F) prior to transport.

Preparation for Courier Transport

Transport: 2.0 mL CSF, refrigerated (2-8°C or 36-46°F). (Minimum: 1.5 mL)

Rejection Criteria

Specimens not collected and processed as indicated.

In-Lab Processing

Transfer CSF into a skirted capped, plastic vial and maintained refrigerated (2-8°C or 36-46°F) prior to transport.

Transport: 2.0 mL CSF, refrigerated (2-8°C or 36-46°F). (Minimum: 1.5 mL)

Storage

After separation, store refrigerated prior to shipment to laboratory.

Laboratory

Sent to Michigan Department of Health and Human Services (MDHHS), Lansing, MI (May-October), or ARUP Laboratories, Salt Lake City, UT (November-April).

Performed

Weekly.
Results available in approximately 7 days.

Reference Range

By report.

Test Methodology

IgM Capture Enzyme Linked Immunosorbent Assay/Microsphere Immunoassay (MIA).

Interpretation

This panel includes: Eastern Equine Encephalitis (EEE), St. Louis Encephalitis (SLE), California Group Virus (CGV), and West Nile Virus (WNV). The presence of IgM antibody in CSF may have diagnostic value. Absence of IgM antibody must be interpreted cautiously.

Clinical Utility

This assay is used in the determination of recent infection by demonstration of IgM antibody in CSF. The presence of IgM antibody may have diagnostic value. Absence of IgM antibody must be interpreted cautiously. St. Louis encephalitis (SLE) and California encephalitis (CE) group viruses are the major mosquito-borne viruses causing human disease in the United States. West Nile encephalitis (WNE) is a close relative of St. Louis encephalitis virus. Eastern Equine encephalitis (EEE) is seen less frequently but is also similar in its seasonal occurrence and overlaps in regional distribution. Human infection by these viruses induces an immune response and specific antibody production against the viral antigens. Since viral isolation attempts from these cases are seldom productive, the majority of human cases are diagnosed by serologic means.

Clinical Disease

Most people infected with West Nile virus have no symptoms of illness, but some may become ill 3 to 15 days after the bite of an infected mosquito. Studies have shown that about 1 in 4 infected persons will have mild illness with fever, headache and body aches, sometimes with skin rash and swollen lymph glands. More severe infection (encephalitis) is less common and may be marked by headache, high fever, stiff neck, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. In a few cases, mostly among the elderly, death may occur. Persons with severe or unusual headaches should seek medical care as soon as possible.

Epidemiology

The risk of getting West Nile encephalitis is limited to persons in areas where virus activity occurs and is higher in persons 50 years of age and older.

Transmission

People get West Nile encephalitis from the bite of a mosquito that is infected with West Nile virus. West Nile virus in NOT transmitted from person to person.

CPT Codes

LOINC:  West Nile Virus (WNV) 29780-4, California Group Virus (CGV) 29829-9, St. Louis Encephalitis (SLE) 49144-9, Eastern Equine Encephalitis (EEE) 43096-7

Contacts

Last Updated

10/17/2023