How many lines indicate a positive antigen test for influenza A?
Mar 20, 2025
Source: Cainiu Health
Dr. Ren Yi
Introduction
Influenza A antigen refers to the antigen test for Influenza A virus. A positive result in the Influenza A antigen test will display two lines. In daily life, it is important to maintain personal hygiene, wash hands frequently with soap or hand wash, and thoroughly clean hands following the seven-step handwashing technique, especially after touching public items, before meals, and after using the toilet. Keep indoor air circulating by regularly opening windows for ventilation to reduce the risk of infection.
Generally, the term "influenza A antigen" refers to antigen testing for Influenza A virus. A positive result for Influenza A virus antigen testing will display two lines. The specific interpretation is as follows:
Influenza A virus antigen test kits typically operate on principles such as the colloidal gold method. The test device contains a test line and a control line. When Influenza A virus antigen is present in the sample, the antigen will bind specifically to antibodies in the test reagent, forming an immune complex on the test line, resulting in a visible color change on both the test and control lines, indicating a positive result. If only the control line appears and the test line does not, the result is negative. If the control line does not appear, regardless of whether the test line appears or not, the test result is invalid and must be repeated.
In daily life, it is important to maintain personal hygiene by washing hands frequently with soap or hand wash, following the seven-step handwashing technique thoroughly, especially after touching public items, before meals, and after using the toilet. Keep indoor air circulating by regularly opening windows for ventilation at least 2-3 times daily for 20-30 minutes each time, to reduce indoor virus concentration and lower the risk of infection.
