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of Nebraskans through diagnostic laboratory
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Testing Results
IMPORTANT! Sites requesting testing must have approval from the appropriate state or local health department before submitting specimens. Approval must be sent to NPHL by email at or by calling (402) 559-9444.

A Special Microbiology Form must accompany the specimens. Some tests require additional forms and patient history. This will be listed below when applicable. When requested, testing will not be performed without all required information.

Please call NPHL Client Services at (402) 559-2440 or toll free at (866) 290-1406 for further clarification.


  Test: Influenza A and B Virus Antibody, IgM 
  Synonym: Influenza Virus Serology 
  Method: Enzyme-Linked Immunosorbent Assay 
  Availability: Monday, Wednesday, Friday; results in 1 - 4 days 
  Specimen: Blood 
  Collection Device: Clot (Red) or SST (Gold) tube 
  Volume: 1 - 4 mL blood 
  Storage/Transport: Separate serum from the cells ASAP; transport and store refrigerated, and if transport > 48 hours, aliquot and freeze 
  Unacceptable: Severly lipemic, icteric or hemolyzed samples; heat-activated serum; multiple freeze thaw cycles 
  Specimen Stability: After separation from cells; ambient, < 8 hours; refrigerated, 48 hours; frozen, 1 year 
  Reference Interval: ≤ 0.89 IV: NEGATIVE - No significant level of influenza A or B virus IgM detected

0.90-1.10 IV: EQUIVOCAL - Questionable presence of influenza A or B virus IgM antibody detected. Repeat testing in 10-14 days may be helpful.

≥ 1.11 IV: POSITIVE - IgM antibodies to influenza A or B virus detected, which may suggest current or past infection. 
  Reportable Disease: A positive result is reportable 
  Comments: While the presence of IgM antibodies suggests current or recent influenza infection, low levels of IgM antibodies may occasionally persist for >12 months post infection or immunization. 
  Revised: 2/13/2012 


If you have questions about proper specimen collection, please call NPHL Client Services at (402) 559-2440 or toll free at (866) 290-1406.