West Nile Virus IgM (ELISA)

Detection of IgM antibodies to West Nile virus in equine serum by IgM-capture ELISA. This test is used to assess recent exposure to West Nile virus in clinically ill equines.

2 mL serum

Collect serum from clotted blood in a non-additive tube (e.g. plain red top or serum separator). When possible, transfer clear serum off the clot into a new tube.

Excessively hemolyzed samples are not acceptable for this test.

Glass or plastic tube with no anticoagulant additives.

Label all samples with unique identifiers. For multiple samples, number tubes consecutively using a permanent marker or adhesive label. Place the tubes in consecutive numerical order in cardboard boxes designated for tubes. Do not submit loose in bags.

Include a list of sample names/numbers or the Excel specimen import spreadsheet with submittal form. 

Use cold packs during hot weather, especially if shipping serum samples on the clot. Overnight shipping is recommended.

Samples must be received in the testing lab / location by 3 p.m., 1 business day before the scheduled test day, otherwise samples will be held until the next scheduled test day.

Please include a clinical history and county of origin for all equine encephalitis serology requests.

This test is most appropriate for assessing recent exposure to WNV in clinically ill equines; please request  West Nile Virus (PRNT) [Referral] for vaccine titers.

This is a test for a disease agent regulated by the Texas Animal Health Commission (TAHC) and/or the United States Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS). Samples, documentation, and testing may be subject to additional requirements or restrictions as determined by TAHC or USDA APHIS.