Influenza Virus Nucleic Acid (RNA) Detection by Qualitative Polymerase Chain Reaction (PCR)

Published: August 9, 2026Updated: August 16, 2026

This test checks for the presence of genetic material from the influenza virus in your respiratory sample, helping diagnose recent or active flu infection.

Quick summary

["A quick way to confirm if the flu virus is causing your symptoms."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC: 104727-3
Short code: FLUAV H1 2009 pand RNA Spec Ql
Synonyms: FLUAV H1 2009 pand RNA Spec Ql
Category: chemistry
Sample: serum
Container: Red-top tube (SST)
Units: N/A
Fasting: false
Population: adult
Sex: all
Age range: 18–65 years
Method: molgen
Specimen volume: 5 mL
Stability: Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max: 500
Lipemia max: 1000
Icterus max: 500
TAT: 4–24 hours
Order: routine

Why This Test Is Done

Your healthcare provider may order this test if you have flu-like symptoms (e.g., fever, cough, sore throat) within days of exposure to the flu. It’s often used to guide treatment decisions, especially in high-risk groups or during outbreaks.

What to Expect Before the Test

You’ll likely provide a nasal or throat swab sample. No special preparation is needed, but avoid eating or drinking immediately before testing if instructed.

What the Test Results Mean

A positive result means the test detected the influenza virus RNA, suggesting you may have an active flu infection. A negative result means the virus wasn’t found in this sample, but you could still be infected or have a different illness.

When You Might Need Follow-Up

If results are positive, your provider may recommend antiviral medications to shorten illness duration or monitor for complications. If negative, they may retest later or check for other causes of your symptoms.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Influenza RNA Test (Qualitative PCR)

Frequently asked questions

How soon after symptom onset can this test detect the flu?

This test can detect the flu virus as early as 1–2 days after symptoms begin, but results may take 24–48 hours to return. Early testing improves the chance of accurate results.

Can this test differentiate between different flu strains (e.g., A, B, or subtypes)?

Yes, this qualitative PCR test identifies the presence of influenza RNA without specifying the exact strain. For strain-specific guidance, additional testing may be needed.

What if I have a weak immune system or other health conditions?

If you’re at higher risk for severe flu complications (e.g., pregnancy, chronic illness), this test helps confirm infection quickly so antiviral treatment can be started promptly.

Sources

1
MedlinePlus — Laboratory TestsSource
2
Lab Tests OnlineSource
3
Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy