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11 Cards in this Set
- Front
- Back
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Describe the genome of HCV.
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(+) ssRNA with an IRES in the 5' NTR.
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How is HCV translated?
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The viral genome has one ORF which is translated as a single polyprotein that is subsequently cleaved by cellular and viral proteases.
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What enzymes does the HCV genome code for?
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*proteases for polyprotein cleavage
*RNA-dependent RNA polymerase |
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How many forms of HCV exist?
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There are 6 genotypes and ~100 subtypes.
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Following acute infection, what clincal presentation does HCV show?
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Most (70-100%) patients convert to chronic carriers who then show sequential episodes of acute inflammation. 40% of these carriers will develop cirrhosis and HCC.
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What is the key immune player in clearance of HCV?
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Interferon
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Why is immunity against HCV typically less than effective? What can be inferred from a positive anti-HCV blood test?
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The virus shows antigenic drift within a single patient ("quasi species") and thus is able to evade immune attacks. The presence of anti-HCV signals ongoing infection and viremia - not recovery.
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How is HCV transmitted?
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*blood
*body fluids *needles *vertically |
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How is HCV diagnosed?
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ELISA for HCV antibodies.
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What problems have been encountered in the development of a vaccine for HCV?
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There are multiple serotypes and even within a single patient there is antigenic drift.
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What treatment is available for HCV? What kind of success is seen?
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Interferon alone or in combination with ribavirin is used. There have been mixed results including supression of viremia with rebound of the virus following discontinuation of therapy.
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