Reasonable mechanisms for viral persistence in infected individuals include all of the following EXCEPT
A. destroy ofimmune cells by viruses
B. virus-mediated inhibition of host DNA synthesis
C. integration of a provirus into the genome of the host
D. host tolerance to viral antigens
E. mutation of viral antigens
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Virus-infected cells often develop morphologic changes referred to as cytopathic effects. Which of the following statements about virus-induced cytopathic changes is most accurate?
A. They are pathognomonic for an infecting virus.
B. They are rarely associated with cell death.
C. They may include giant cell formation.
D. They can only be seen with an electron microscope.
Laboratory infections can be acquired when working with viruses unless good laboratory safety practices are followed. Which of the following is not a good biosafety practice?
A. Use of biosafety hoods
B. Use of laboratory coats and gloves
C. Avoidance of pipetting by mouth
D. Flushing experimental waste down laboratory sink
E. Not eating or drinking in the laboratory
Which one of the following is a fundamental principle of viral disease causation?
A. One virus type induces a single disease syndrome.
B. Many viral infections are subclinical and do not produce clinical disease.
C. The type of disease produced by a virus can be predicted by the morphology of that virus.
D. A particular disease syndrome has a single viral cause.
E. Social factors do not influence the occurrence of viral diseases.
During the incubation period of an acute systemic virus infection, ( )
A. characteristic signs of virus infection appear
B. infectious virus cannot be isolated from any tissues
C. infectious virus cannot be shed
D. the host's immune response is stimulated by viral antigens
E. virus is limited to the site of inoculation
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