Epidemic Influenza A detection and subtyping (test code FLUPCR)

This test detects and reports each of the following influenza A virus subtypes:

Contents

Specimen requirements

See Specimens for instructions on specimen collection and training resources including a training video.

Please provide one of the following:

Nasopharyngeal (NP) swab
Recommended swab: flocked, mini-tip swab broken into a screw top vial with UTM or other viral transport medium.
The recommended swab is provided in a NP swab collection kit soon available from hospital materials management, see Specimens.
Other swabs with plastic shafts may be substituted.

Swabs on wire shafts
Dry plastic or wire swabs (without viral transport medium) are acceptable, but are somewhat less sensitive and therefore not recommended.

For other specimen types, please contact the Laboratory Medicine Resident on Call via the UWMC paging operator (598-6190)

Specimens must be accompanied by a Lab Medicine requisition.

The appropriate requisition may be included in the NP swab collection kit.
A printable requisition may also be downloaded: FLUPCR_requisition.pdf
The requisition was last modified 10/09/2009 Note: please compare this date to the version indicated on the requisition, and refer to this page for the most recent version.
Specimen processing information for the laboratory is available in the Online test guide entry for FLUPCR

24-48 hours once specimen is in the lab (test is performed once a day, Monday through Saturday).
Note: Respiratory Fluorescence Antibody (FA) testing is performed 7 days a week and will also detect Influenza A
Online test guide entry for Respiratory FA

Influenza A PCR Screen
- Positive if any strain(s) of influenza A virus is/are detected.
- Rarely the Influenza A PCR screen is positive and all subtyping PCRs are negative. This result should be be interpreted as positive for influenza A. This apparent discrepency may occur when the viral load in the sample submitted is near the threshold of detection.
Influenza A PCR subtyping
- 2009 Swine H1N1 Influenza A: Positive when the 2009 swine-origin influenza A is detected.
- H1N1 seasonal influenza: Positive when the seasonal H1N1 influenza A is detected.
  - Note: H1N1 seasonal influenza is different from H1N1 Swine-origin influenza. This virus is a common cause of seasonal influenza. The seasonal flu vaccine protects against seasonal H1N1 and H3N2 influenza viruses.
- H3N2 seasonal influenza: Positive when the seasonal H3N2 influenza A is detected.