Micro Hepatitis A, C And E Viruses

Front 1

What family of virus:
1. HAV
2. HBV
3. HCV
4. HDV
5. HEV
6. HGV

Back 1

1. picornavirus
2. hepadna
3. flavi
4. delta
5. calici
6. flavi

Front 2

which two hepatitis viruses are flaviviruses?

Back 2

HCV and HGV

Front 3

Are all hepatitits viruses ssRNA?

Back 3

No, HBV is dsDNA virus
All others ss (+) RNA except HDV (-)

Front 4

Which hepatitis viruses are transmitted via the fecal-oral route?

Back 4

HEV and HAV
(“Eating off your Ass” gives you Hep E and A)

Front 5

Which hepatitis viruses are transmitted percutaneous/blood, sexually and perinatally?

Back 5

Hep BCDG (A may also be sexually transmitted)
“Blood, Cuts, Drugs, Going-to-be-a-baby (in utero)”

Front 6

which hepatitis viruses have a carrier state?

Back 6

Hep BCD (G likely)

“Blood, Cuts, Drugs, and likely Going-to-be-a-baby (in utero)”

Front 7

which hepatitis virus is most commonly in adults rather than kids?

Back 7

HCV

Front 8

What’s the prognosis for hepatitis forms A-G?

Back 8

A. excellent
B. variable
C. variable
D. acute=good, chronic =poor
E. good
G. ??

Front 9

which forms of hepatitis commonly lead to a chronic state?

Back 9

HBV in infants (80-95%; only 1-10% in adults)
HCD (70-80% chronicity rate) and HDV (70-80% in superinfection of HBV)

Front 10

What causes hepatitis?

Back 10

caused by multiple agents
hepatitis viruses cause the majority of cases.

Front 11

Which viruses can cause hepatitis?

Back 11

hepatitis viruses A-G--which target the liver
Epstein Barr virus
yellow fever virus
cytomegalovirus, which target the liver and other organs.

Front 12

What are very common causes of Hepatitis?

Back 12

Hepatitis A and C viruses --very different viruses and cause very different types of hepatic disease.

Front 13

What kind of virus is Hepatitis A?

Back 13

member of the Picornaviridae family, Heparnavirus genus.

Front 14

What kind of virus is Hepatitis C?

Back 14

member of the Flaviviridae family
originally called “non-A, non-B hepatitis virus” (NANB) when serologic tests ruled out HAV and HBV as the causative agents of cases of hepatitis.

Front 15

What kind, genus and family of virus is Hep A?

Back 15

hepatovirus,
Heparnavirus genus
Picornaviridae family.

Front 16

Structure of Hep A virus?

Back 16

1. Non-enveloped (naked) with a single-stranded, (+)-sense RNA genome.
2. Virions are icosahedral and even more stable than other picornaviruses; resistant to
inactivation by heat, detergent, low pH, and desiccation.

Front 17

What kind of genome does Hep A have?

Back 17

Non-enveloped w/ ss (+)sense RNA

Front 18

How do Hep A viruses replicate?

Back 18

1. Replicates like other picornaviruses.
a. Binds receptor on liver cells and a few other cell types.

2. Is NOT cytolytic, released by exocytosis.

Front 19

What kind of disease does hep A most commonly cause?

Back 19

~40% of acute hepatitis cases caused by HAV.

Front 20

How is Hep A transmitted?

Back 20

fecal-oral route and spreads quickly.

Front 21

How fast does Hep A spread?

Back 21

Spreads quickly b/c:
a. most infected people are contagious before symptoms appear.
b. 90% of children and 25-50% of adults have inapparent, but productive infections.
c. virus is released into stool at high concentrations.

Front 22

How tough is hep A Virus?

Back 22

it can survive in fresh and salt water for many months.

Front 23

What causes hep A outbreaks?

Back 23

.HAV outbreaks usually due to a “common source” like contaminated water or raw shellfish, or infected individuals. Infected food handlers, daycare workers, children have the potential to infect many other people.

Front 24

Who gets HAV most frequently?

Back 24

Children (schools, camps)

Front 25

Where and when is HAV found?

Back 25

Worldwide, all year-long.

Front 26

Why is HAV rarely spread via blood?

Back 26

viremia is low and No chronic infections w/ HAV

Front 27

Can HAV cause chronic hepatitis?

Back 27

NO

Front 28

How does HAV infect?

Back 28

Ingested,
then probably replicates in the GI tract (oropharynx or epithelial lining of the intestines),
then enters the bloodstream

Front 29

Where does HAV replicate?

Back 29

parenchymal cells of liver--hepatocytes and Kupffer cells.

Front 30

Before jaundice or Ab detection, where can HAV be found?

Back 30

released from cells into bile and then into stool.
shed in high concentration into stool ~10 days before jaundice or antibody can be detected.

Front 31

When HAV replicates in liver cells what happens to the cell?

Back 31

Replication is NOT cytopathic, immune response to HAV is thought to result in immunopathogenesis.
Antibody, complement, ADCC contribute to lysis of infected cells and liver damage (icterus).

Front 32

What’s icterus?

Back 32

liver damage signified by yellow discoloration of skin and mucous membranes (jaundice)

Front 33

What causes liver damage w/ HAV?

Back 33

Immune system response to the virus
Specifically: Ab, complement, ADCC cause lysis of infected cells

Front 34

How many serotypes does HAV have?

Back 34

1

Front 35

what kind of protection does an individual have after HAV infection?

Back 35

lifelong due to IgG antibodies induced by infection provide lifelong protection against
re-infection (only 1 serotype)

Front 36

does HAV produce chronic infections?

does HAV cause immune complex-related syndromes, like rash or arthralgia?

Back 36

no


no

Front 37

How is severity of HAV infection in kids vs adults?

Back 37

milder in children than in adults and usually asymptomatic.

Front 38

Time course of HAV infection?

Back 38

incubation period is 3-4 weeks followed by initial Sx
virus shed in stool 2 wks before Sx appear, stop before Sx appear
symptoms abrupt 15-50 days after exposure
Sx intensify 4-6 d before icteric phase

Front 39

What are the Initial symptoms of HAV infection?

Back 39

fever, fatique, nausea, loss of appetite, abdominal pain.

Front 40

When do Sx of HAV infection occur?

Back 40

Symptoms occur abruptly 15-50 days after exposure and intensify for 4-6 days before icteric phase.

Front 41

What are the Symptoms of HAV infection?

Back 41

similar to those of other hepatitis virus which cause liver damage due to immunopathogenesis:
dark urine
pale feces
elevated liver enzymes.

Front 42

When is HAV shed in stool? When does it stop?

Back 42

up to 2 weeks before symptoms appear
stops before symptoms disappear.

Front 43

Prognosis for HAV infection?

Back 43

Complete recovery occurs in 99% of cases.

Fulminant hepatitis occurs in 1-3 persons per 1000 infected with HAV and is associated with 80% mortality rate.

Front 44

How common is fulminant hepatitis due to HAV?

Back 44

1-3 : 1000 infected w/ HAV
80% mortality

Front 45

How is HAV infection diagnosed?

Back 45

a. time course of clinical symptoms,
b. identification of known infected source,
c. specific serologic tests.

Front 46

What are some specific serological tests to diagnose HAV?

Back 46

Detection of anti-HAV IgM indicates acute HAV infection
detection of anti-HAV IgG indicates a previous HAV infection (or vaccination) and immunity to re-infection.

Front 47

What does anti-HAV IgM indicate?

Back 47

Acute HAV infection

Front 48

What does anti-HAV IgG indicate?

Back 48

Previous HAV infection or vaccination
Immune to reinfection

Front 49

How is HAV infection prevented after exposure?

Back 49

80-90% effectiveness by prophylaxis with immune serum globulin (passive immunization) given before or early after exposure (<2 weeks).

Front 50

What kind of vaccine is given to prevent HAV?

Back 50

A killed (inactivated) HAV vaccine is available

Front 51

Who is the killed HAV vaccine recommended for?

Back 51

a. people living in or traveling to areas where HAV is endemic,
b. children 2-18 years old,
c. men who have sex with men.

Front 52

How is HAV vaccine given?

Back 52

2 doses: an initial dose and a booster 6-12 months later.

Front 53

What are some ways to prevent spread of HAV?

Back 53

good hygiene
avoid potentially contaminated food and water.

Front 54

What kind of virus and family is HCV?

Back 54

member of Hepaciviridae group
Flaviviridae family.

Front 55

Structure of HCV?

Back 55

Enveloped w/ icosahedral capsid and single-stranded, (+)-sense RNA genome.

Front 56

What kind of genome does HCV have?

Back 56

ssRNA, (+) sense
(same as HAV)

Front 57

How does HCV replicate?

Back 57

1. not very well understood.
2. in the cytoplasm.
3. Viral genome translated into a single polyprotein , then cleaved by viral protease into individual viral proteins.
4. Virions bud from ER (release mechanism unclear)

Front 58

What’s the reservoir for HCV?

Back 58

Humans

Front 59

How is HCV transmitted?

Back 59

primarily through blood.
(most prevalent blood-borne pathogen in U.S.--4.9 million people are infected; 200 million worldwide)

Most cases via contaminated needles (i.v. drug use).

Front 60

How are blood donations screened for HCV?

Back 60

Screen for HCV and HCV antibodies.

Front 61

What are some ways HCV transmission can occur w/ blood donations?

Back 61

i. contaminated, pooled immune globulin
ii. organ donations
iii. factors VIII or IX given to hemophiliacs.

Front 62

Who is infected w/ HCV?

Back 62

Almost all HIV-infected individuals who were or are i.v. drug users are infected with HCV.

Front 63

What’s the problem w/ chronic HCV in the population?

Back 63

High incidence of chronic asymptomatic infections results in frequent transmission to others.

Front 64

Where does HCV replicate?

Back 64

Hepatocytes (NOT cytopathic.)
Many infections become chronic (persistent).

Front 65

How is HCV infection controlled?

Back 65

Hepatocytes are killed by immune attack by CTLs.

Front 66

Which hepatitis virus infection causes increased frequency of hepatocellular carcinoma?

Is it a viral oncogene?

Back 66

HCV infection due to increased cell division and mutation

not a viral oncogene.

Front 67

What increases the rate of Hepatocellular carcinoma in HCV infected individuals?

Back 67

alcoholism enhances frequency of HCC in HCV-infected

Front 68

Is there a humoral immune response to HCV?

Back 68

Kinda, Ab’s are made, but are not protective.

Front 69

How commonly does HCV lead to chronic infection?

Back 69

~70% of patients are chronically infected and continue to produce virus for at least 1 year.

Front 70

Can re-infection occur w/ HCV once the virus is cleared?

Back 70

not known if reinfection can occur or whether there is lifelong immunity.
(~70% of pts are chronically infected)

Front 71

What are 3 types of liver disease caused by HCV?

Back 71

1. Acute hepatitis w/ virus clearance and recovery (~15% cases)
2. Chronic persistent infection w/ disease progression later (~70%)
3. Severe rapid progression to cirrhosis (15% chronic cases)

Front 72

How often does HCV cause acute hepatitis with virus clearance and recovery?

Back 72

~15% of cases

Front 73

What are the symptoms of acute HCV infection?

Back 73

similar, but milder than w/ acute HAV and HBV infections
inflammatory response less intense.
Sx: fever, anorexia, nausea, vomiting and jaundice.

Front 74

What happens most often w/ initial HCV disease?

Back 74

Disease inapparent and leads to chronic persistent disease.

Front 75

How often does HCV cause chronic persistent infection with progression to disease later in life?

Back 75

~70% of cases

Front 76

what’s the progression like to chronic hepatits w/ HCV?

Back 76

Progress to chronic active hepatitis w/in 10-15 years.
Cirrhosis and liver failure after 20 years = most common indicator for liver transplantation.
Hepatocellular carcinoma (HCC) after 30 years in < 5% of cases.

Front 77

How common is hepatocellular carcinoma in those infected w/ chronic HCV?

Back 77

After ~30 yrs of chronic HCV infection < 5% of cases develop HCC

Front 78

How common is severe rapid progression to cirrhosis w/ HCV infection?

Back 78

~15% of chronic cases

Front 79

How is HCV diagnosed in the lab?

Back 79

1. detection of anti-HCV antibodies by ELISA.
2. RT-PCR is used to detect HCV genome in serum, blood supply, etc.
3. elevated liver enzymes in chronic infection (detect HCV Ab’s and HCV RNA for at least 6 months)

Front 80

What do you need to know about detecting HCV Ab’s by ELISA?

Back 80

Seroconversion occurs within 7-31 weeks of infection.
Ab’s not always detectable in viremic or immunocompromised, or individuals on hemodialysis.

Detect HCV Ab’s and HCV RNA for >6 mo for chronic infection

Front 81

How is HCV infection treated?

Back 81

w/ alpha interferon, pegylated interferon (Peg-intron) and ribavirin.

Front 82

What do alpha interferon, pegylated interferon (Peg-intron) and ribavirin treatments do for HCV infection?

Back 82

a. reduce viral replication and liver damage, but don’t eliminate carrier state.
b. Associated w/ S/E’s (may limit their use in combo)

Front 83

how is transfusion-acquired HCV prevented?

Back 83

screening

Front 84

How is HCV prevented?

Back 84

NO vaccine
Screen transfusion blood, etc

Front 85

Can pooled immune serum globulins be given for postexposure prophylaxis?

Back 85

No, they’re ineffective.

Front 86

Can HAART (highly active anti-retroviral therapy) be used for HCV infection?

Back 86

HAART may exacerbate hepatitis in patients co-infected with HIV and HCV.

Front 87

What does HEV commonly cause?

Back 87

E causes Enteric Dz

Major cause of enterically transmitted hepatitis
epidemics in Asia, Africa, India, and Mexico.

Front 88

What are the symptoms and disease produced by HEV infection?

Back 88

Resembles HAV:
1. Higher mortality rate in pregnant women than with HAV.
2. Does not cause chronic infection.

Front 89

How is HEV diagnosed?

Back 89

Exclude other hepatitis viruses b/c lab tests not readily available.

Front 90

How is HEV treated/prevented?

Back 90

No treatment or vaccine.

Front 91

Where was HGV found? What does it cause?

Back 91

Isolated from a patient with post-transfusion hepatitis, but has not been shown to cause hepatitis.
Can cause a chronic infection lasting for decades.

Front 92

If you get HGV, what’s the prognosis?

Back 92

~60-70% of those infected clear the virus and develop Ab’s
not shown to cause hepatitis
can cause chronic infection lasting for decades

Front 93

How is HGV transmitted?

Back 93

sexual intercourse and blood

Front 94

Where is HGV found?

Back 94

in the blood of millions of people worldwide.
U.S—in blood from 2% random blood donors, 15% of HCV-infected individuals, and 35% of HIV-infected individuals.

Front 95

What kind of interaction does HGV have w/ HIV?

Back 95

May interfere with replication of HIV and increase lifespan of coinfected individuals.

Front 96

What virus family does HGV belong to?

Back 96

Member of the Flaviviridae family, like HCV, enveloped, single-stranded, (+)-sense
RNA genome. Also known as GB virus.

Front 97

What kind of virus/family is HEV?

Back 97

Non-enveloped w/ ss (+)-sense RNA genome
Tentatively classified as member of the Caliciviridae family.