Question

The clumping of test cells indicates a negative test result in the

A) viral hemagglutination inhibition test.
B) precipitation test.
C) indirect agglutination test.
D) complement-fixation test.
E) direct agglutination test.

Answer 1

A negative result in the viral hemagglutination inhibition test is indicated by the clumping of test cells, implying the presence of virus-specific antibodies that prevent the virus from causing hemagglutination. Option A.

Step-by-step explanation:

The clumping of test cells indicates a negative test result in a viral hemagglutination inhibition test (A). This assay is commonly used to determine the presence of virus-specific antibodies in a patient's serum, which inhibit the hemagglutination process that would typically be caused by viruses.

In a hemagglutination inhibition assay, the patient's serum is mixed with a standard amount of virus and red blood cells.

When virus-specific antibodies are present, they bind to the virus and prevent it from agglutinating with the red blood cells, resulting in the presence of a red dot at the bottom of the well, indicating a negative result for viral presence and a positive identification of neutralizing antibodies.

So Option A is correct.