Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
75 Cards in this Set
- Front
- Back
Virus family of Hep A
|
Picornaviridae
|
|
Virus family for Hep B
|
Hepadnaviridae
|
|
Virus family for Hep C
|
Flaviviridae
|
|
Virus family for Hep E
|
Caliciviridae
|
|
Type of virus Hep D is
|
Defective ssRNA virus
|
|
What causes cellular damage in hepatitis?
|
The Immune Response
Actual virus growth is relatively benign for hepatocytes |
|
% of Hep B carriers that develop chronic, active hepatitis
|
25%
|
|
Predominant Hep B serotype in the U.S.
|
adw
|
|
HBV can be disinfected by
|
Bleach
Acid |
|
Unlike most enveloped viruses, HBV CANNOT be inactivated by these
|
Detergent
Ether |
|
Dane particle
|
Name for the infectious virion of HBV
|
|
Size of the two particles that accompany Dane particle
|
20 nm
One is a rod, one is a sphere |
|
What are the two particles that accompany the Dane particle made of?
|
Composed entirely of S glycoprotein (HBsAg)
|
|
Unique characteristic of Hepatitis virus
|
PARTIALLY double stranded
Full length minus strand 50-80% complete positive strand |
|
What are the four proteins encoded by HBV?
|
HBsAg
HBcAg Polymerase Protein X (function unknown) |
|
What is special about HBV polymerase?
|
Has BOTH RNA-dependent and DNA-dependent (reverse) polymerase activities
|
|
Three forms of HBsAg
|
Small
Medium Large ALL are present in virions |
|
Predominant form of HBsAg in Dane, spherical and rod-shaped particles
|
Small form
|
|
HBeAg
|
Truncated form of HBcAg that is secreted by infected cells
Function is unknown |
|
In what cells does HBV replication take place?
|
Hepatocytes
|
|
Where in the cell does HBV replication take place?
|
Nucleus
|
|
cccDNA
|
Covalently Closed Circular DNA
This is what HBV DNA becomes after missing nucleotides of + strand are added |
|
Where is the + strand of the DNA made complete?
|
In the nucleus
|
|
What is packed in the initial capsid with the full-length transcript?
|
Core protein
HBV Polymerase NOTE: remember that the transcript is RNA |
|
Inside the capsid, what is done with the transcript?
|
Complete MINUS DNA strand is synthesized from it
Minus strand DNS is template for incomplete PLUS strand DNA |
|
What does HBV bud through?
|
Cytoplasmic VESICLE
|
|
How does HBV exit the host cell?
|
Exocytosis
|
|
How is HBV transmitted?
|
Parenterally (needles, sex, birth, etc.)
HBV present in all body fluids, including mother's milk |
|
Is rate of progression to chronic infection higher in children or adults?
|
Children (80-95%)
In adults, it is only 5-10% |
|
Incubation period for HBV
|
Two months or more
|
|
Are there more virions or 20 nm particles in blood?
|
20 nm particles
|
|
"Window period" of HBV infection
|
When neither HBsAg nor anti-HBs can be detected
After HBsAg has largely disappeared Before anti-HBs has shown up NOTE: Abs for HBc and HBe are detectable in this period |
|
Serology of HBV chronic carriers key characteristics
|
HBsAg does NOT go away
Anti-HBs never shows up |
|
In what order do the following show up?
Anti-HBs, Anti-HBc, Anti-HBe |
Anti-HBc --> Anti-HBe --> Anti-HBs
NOTE: in chronic carrier state, Anti-HBs never shows up |
|
When (what period) does Ab for HBsAg show up?
|
During the recovery period
SO, it doesn't contribute significantly to clearing |
|
In an HBV infection, what do CD8 T cells recognize?
|
Fragments of HBcAg
|
|
Where (in the world) is HBV carrier rate high?
|
Southeast Asia
Africa |
|
Type of vaccine for HBV
|
Subunit vaccine consisting of HBsAg
Given in three doses |
|
Most widely used drug against HBV
|
Lamivudine
|
|
Timeline of HBV dosage
|
1st dose is time 0
2nd dose 1 month after first 3rd dose 6 months after first |
|
What is given to babies right after birth to prevent HBV?
|
HB immune globulin
|
|
HDV is also known as what?
|
Delta agent
|
|
HDV requires what other virus in order to propagate?
|
HBV
|
|
When is disease more severe?
HDV and HBV simultaneous co-infection OR HDV super-infection in an HBV carrier |
HDV super-infection in an HBV carrier
Rate of fulminant hepatitis is greater Progression to carrier state occurs to greater extent |
|
Characteristics of HDV genome
|
MINUS sense
ssRNA Enclosed in capsid of Delta antigen Wrapped in membrane containing HBsAg |
|
What one protein does HDV genome encode?
|
Delta antigen
|
|
How is HDV transmitted?
|
Same as HBV
EXCEPT, NOT by sexual route |
|
What is the only real method to control HDV?
|
Vaccination for HBV
|
|
What is the etiological agent for "acute" (infectious) hepatitis?
|
Hepatitis A
|
|
How many serotypes of HAV are there?
|
Only ONE
|
|
How is HAV transmitted?
|
Fecal-oral route
|
|
HAV is inactivated by... (5)
|
Bleach
Formalin Beta-propriolactone UV radiation Routine chlorination of drinking water |
|
Large quantities of HAV can be found where (in/from body)?
|
In bile
In stool |
|
Onset of symptoms in HBV is described as
|
Insidious
|
|
Onset of symptoms in HAV is described as
|
Acute
|
|
Incubation period for HAV
|
Approximately 4 weeks
|
|
After recovery from infection, what is HAV immune status of pt.?
|
Life-long immunity
There are NO CHRONIC CARRIERS |
|
What is the course of HAV hepatitis?
|
Symptoms last for 3-4 weeks
Infection resolves completely |
|
How is HAV diagnosed?
|
Analyzing stool w/ PCR or immunoassay
ELISA assay for anti-HAV in blood |
|
Is HAV more symptomatic in adults or children?
|
Adults (3:1, symptomatic:asymptomatic)
Children (1:12) |
|
Type of vaccine for HAV
|
Killed
|
|
In the U.S. are there more carriers for HBV or HCV?
|
3x as many HCV carriers
|
|
HCV-encoded proteins do what to the immune response?
|
Antagonize it
Inhibit apoptosis Antagonize effect of interferon |
|
How is HCV transmitted?
|
Parenterally (Sex, blood, needles)
|
|
Incubation period for HCV
|
1 - 2 months
|
|
When can viremia be detected in an HCV-infected pt.?
|
After 1 - 3 WEEKS
Lasts 4-6 months in those who clear infection Last for life in chronically infected |
|
How long does it take for most pts. to become anti-HCV positive?
|
Usually happens within 5 MONTHS (7 - 31 weeks)
|
|
% of people who become HCV chronic carriers
|
85%
|
|
This enhances the progression of HCV chronic carriers to liver disease
|
Alcohol abuse
|
|
% of deaths from chronic liver disease attributed to HCV
|
40%
|
|
This has been successful in clearing carrier state of HCV in some pts.
|
Combo of interferon and ribavirin
|
|
Pt. group at risk for severe HEV infection
|
Pregnant women
20% mortality in this group |
|
Hepatitis viruses with parenteral transmission
|
HBV
HCV HDV |
|
Hepatitis viruses with fecal-oral transmission
|
HAV
HEV |
|
Hepatitis C genotype that is most common in U.S.
|
Genotype I
Shows poor response to treatment |