18. Viruses, Viroids, & Prions

A clear area against a confluent "lawn"of bacteria is called a:

The approximate viral concentration of a sample is known as:

Which of the following statements accurately describes viral plaques?

Test used to detect the presence of antibodies in a patient’s serum.

a. Direct fluorescent antibody

b. Indirect fluorescent antibody

c. Rabies immune globulin

d. Killed rabies virus

e. None of the above

In an agglutination test, eight serial dilutions to determine antibody titer were set up: Tube 1 contained a 1:2 dilution; tube 2, a 1:4, and so on. If tube 5 is the last tube showing agglutination, what is the antibody titer?

a. 5

b. 1:5

c. 32

d. 1:32

The patient has a viral titer of 200 on day four after infection, 30 at 4 weeks after infection, 600 at 8 months after infection, and 23 after 1 year of infection. This is likely a(n) _______________ infection.

Which of the following could inform you if your patient had a previous infection with a nonpersistent virus and recovered? Select all that apply.

a. A PCR test

b. A plaque assay

c. An ELISA test

d. An agglutination assay

A young man comes into your clinic and asks for an HIV test. He had unprotected sex two weeks ago and is nervous. His best option would be a(n):

a. ELISA of anti-HIV antibodies

b. Test that detects HIV genes

c. Latex agglutination test

d. Cell culture of blood sample