Dedicated to protecting the health and safety
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, IgG 
  Synonym: Influenza Virus Serology 
  Method: Enzyme-Linked Immunosorbent Assay 
  Availability: Monday, Wednesday, and 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; for > 48 hours, freeze 
  Unacceptable: Severely 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 levels of influenza A or B virus IgG detected

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

≥ 1.11 IV: POSITIVE - IgG antibodies to influenza A or B virus detected, which may suggest current or past infection 
  Reportable Disease: A four-fold or greater rise in influenza virus antibody titer between the acute and convalescent sera is reportable 
  Comments: Confirmation of influenza by detection of IgG antibody levels requires testing of paired sera. Acute and convalescent sera with index values of < 0.90 and > 1.10, respectively, have been shown to represent a ≥ 4-fold increase in titer. 
  Revised: 2/2/2012 


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