Lab Dept:

Microbiology/Virology

Test Name:

NOVEL A H1N1 INFLUENZA BY PCR

General Information

Lab Order Codes:

H1N1

Synonyms:

H1N1 by PCR, Swine Flu by PCR

CPT Codes:

No charge

Test Includes:

Detection of Novel A H1N1Influenza (swine like) by PCR reported as positive or negative.

Logistics

Test Indications:

Useful for detection of Novel A H1N1 Influenza on patients with influenza-like illness (ILI) who meet MDH criteria for testing.

Lab Testing Sections:

Virology – Sendouts

Referred to:

Minnesota Department of Health (MDH)

Phone Numbers:

Minneapolis:

Saint Paul:

612-813-5806

651-220-6550

Test Availability:

Daily, 24 hours

Turnaround Time:

1-5 days

Special Instructions:

• Ordering provider is required to fill out the Patient Screening Form to determine if the patient if eligible for H1N1 Novel influenza testing (this form will need to be sent with the specimen once the patient is eligible for testing). MDH will not accept specimens for testing without this form.
• Submitted specimens that do not meet testing criteria will not be tested at MDH.
• If a cluster of cases or a patient with concerning circumstance is identified, call MDH epidemiology at 651-201-5414 for consultation.

Specimen

Specimen Type:

Nasopharyngeal swab or Nasal wash/aspirate is preferred. If these specimens cannot be collected, a combined nasal swab with an oropharyngeal swab is acceptable. For patients who are intubated, an endotracheal aspirate should ALSO be collected.

Container:

Swab transport system, sterile container, viral transport media (M4 VTM)

Processed Volume:

1 – 2 mL washing/aspirate; 1 nasopharyngeal swab

Collection:

Nasopharyngeal:

1. Obtain specimens using 1 NP swab (i.e., MiniTip Culturette).
2. Gently insert swab through nose into posterior naspopharynx.
3. Gently rotate swab slowly for 5 seconds to absorb secretions.

Nasopharyngeal Washings:

1. Tilt patient’s head back at a 70° angle.
2. Insert rubber bulb syringe containing 1.0 - 2.0mL of sterile saline until it occludes the nostril.
3. Collect specimen (Minimum: 1.0 mL) with one complete squeeze and release bulb.
4. Repeat in other nostril.
5. Place aspirate in container and forward promptly.

Nasal Aspiration:

1. Prepare suction set up on low to medium suction.
2. Wash hands and put on protective barriers (e.g., gloves, gown, mask).
3. Place child supine and obtain assistant to hold child during procedure.
4. Attach luki tube to suction tubing and #6 French suction catheter.
5. Insert catheter into nostril and pharynx without applying suction.
6. Apply suction as catheter is withdrawn. If necessary, suction 0.5 – 1.0 mL of normal saline through catheter in order to clear the catheter and increase the amount of specimen in the luki tube

Special Processing:

Lab staff:

1. Enter Specimen Source as NW (Nasal Wash) or NP (Nasopharyngeal Swab) in Orders.

2. Place specimen into VTM, refrigerate.

3. Fill out the “MDH Request for Testing and Submission of Isolates” form to include the following information:

a. Write "Project #493” in the upper right-hand corner of form. b. Under Submitting Lab Comment: include lab result, rapid influenza test result & kit name, indicate "Test Requested" as H1N1 Novel Influenza Testing, the "Unusual Case Submission" reason if appropriate. c. There is NO fee sticker required.

This form and the Clinician Screening form (filled out by the ordering provider) MUST accompanied the specimen to MDH.

4. Send specimens using a cold pack and requisition to:

Minnesota Department of Health Public Health laboratory Attn: Biological Accessioning 601 Robert St N St Paul, MN 55155

Transport/Storage

Transport to the Microbiology Laboratory immediately. Store refrigerated.

Note: If specimen cannot be transported to the laboratory immediately. Place specimen in viral transport media (VTM) and refrigerate.

Sample Rejection:

If patient does not meet testing criteria; Specimen with a transit time exceeding 2 hours after collection; specimen not submitted in appropriate container; improperly labeled specimen; insufficient volume; external contamination. If an unacceptable specimen is received, the physician will be notified before the specimen is discarded.

Interpretive

Reference Range:

Negative

For more information, please see the following reference link: Fact Sheet for Healthcare Providers: Interpreting Swine Influenza RT-PCR Detection Panel Test Results, CDC May 2,2009

Critical Values:

N/A

Limitations:

• Negative results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other patient management decisions. A negative RT-PCR test should not be interpreted as demonstrating that the patient does not have novel influenza A (H1N1) infection, if other aspects of the patient’s clinical presentation or recent epidemiologic exposures indicate novel influenza A (H1N1) infection is likely, and diagnostic tests for other causes of acute respiratory illness are negative.
• The test has been designed to minimize the likelihood of false positive test results. However, should false positive results occur, risks to patients could include a recommendation for quarantine of household or other close contacts, a recommendation for patient isolation that might limit contact with family or friends, the ability to work, or the ability to receive certain medical care, prescription of an antiviral drug or other therapy, or other unintended adverse effects.

Methodology:

Polymerase Chain Reaction (PCR)

References:

Minnesota Department of Health July 2009