||Influenza A and B Virus Antibody, IgM
||Influenza Virus Serology
||Enzyme-Linked Immunosorbent Assay
||Monday, Wednesday, Friday; results in 1 - 4 days
| Collection Device:
||Clot (Red) or SST (Gold) tube
||1 - 4 mL blood
||Separate serum from the cells ASAP; transport and store refrigerated, and if transport > 48 hours, aliquot and freeze
||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
||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.