Dialysis Technician Practice Exam

What indicates you have the actual disease?

1. Antibody

2. Antigen

3. Vaccine

4. Immunity

The correct answer is: Antigen

The presence of an antigen in the body indicates that you have the actual disease. Antigens are substances that trigger an immune response; they are often parts of pathogens such as viruses or bacteria. When a pathogen enters the body, it carries specific antigens that can be recognized by the immune system. In the context of an active infection, the detection of antigens suggests that the infectious agent is present, and therefore, the individual has the disease. This is crucial in clinical diagnostics, as testing for specific antigens can help confirm an active infection. In contrast, antibodies (the first choice) indicate a past infection or response to a vaccine rather than the presence of the disease itself. A vaccine is a preventive measure to induce immunity but does not indicate current disease state. Immunity refers to the body's ability to resist a specific infection or disease, which can occur from previous exposure or vaccination, but again does not signify the presence of the disease at that moment. Thus, the detection of antigens is the most direct sign of having the actual disease.