0 a test to see if someone has a particular antigen (= a substance that causes the body's immune system to react) in their blood, body waste, etc., as a way of seeing whether they have a particular condition:
The main advantage of an antigen test over an antibody test is that the foreign antigen is present right away. In contrast it can take time to develop antibodies after infection begins.
In the majority of our patients, PIV3 infection was diagnosed by means of viral antigen tests.
New opportunities for mapping the distribution of the disease have opened up with a simple antigen test, which can be performed with a finger prick drop of blood.
Patients may be found to have H pylori infection based on urea breath tests, stool antigen tests, or endoscopic biopsies.