Fluorescent Immunoassay for Viral RNA (e.g., Influenza A/B)

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms like fever, cough, sore throat, body aches, or fatigue—especially if you’ve been exposed to flu. It’s often used during flu season or in outbreaks to quickly identify active infections in patients, healthcare workers, or communities.

How the Test Works

A small sample of your respiratory secretions (e.g., nasal swab or throat wash) is collected. The test uses a fluorescent immunoassay to detect specific viral RNA fragments. If flu RNA is present, the assay will produce a detectable signal, confirming infection.

Sample Collection and Preparation

The sample is collected by a healthcare professional using a swab or liquid-based method. The sample is then processed in a lab and analyzed for viral RNA without needing to grow the virus in a lab first.

Test Limitations and Considerations

This test only identifies flu RNA and does not distinguish between different flu strains (A or B) or rule out other respiratory viruses. A positive result means you likely have an active flu infection, but symptoms may take a few days to develop. Results can sometimes be false-negative if collected too early or if the sample isn’t handled properly.