Anti-Human Influenza A and B Virus Hemagglutination Inhibition Antibody Titration (Serum/Plasma)

What This Test Measures

The test detects antibodies that your immune system produces in response to exposure to influenza A or B viruses. These antibodies help your body recognize and fight off the virus if you encounter it again. The result is expressed as a titer value, which indicates the strength of your immune response.

Why It’s Done

Your healthcare provider may order this test if you’ve had recent exposure to the flu, if you’re planning to travel to areas with high flu activity, or if you’re at higher risk for complications from influenza (e.g., elderly adults, young children, or those with chronic health conditions). It can also be used to assess immunity before vaccination or after a flu infection.

How the Test Works

Blood is drawn and tested using an immunoassay method to identify specific antibodies against influenza A and B. The test measures the concentration of these antibodies, which helps determine if your immune system has mounted a response.

What to Expect Before the Test

No special preparation is needed. You may eat and drink normally before the blood draw. If you’re on blood-thinning medication, let your provider know before the test.