Body As Host Test #2 Hepatitis Viruses

Front 1

Hepatitis A-Family?

Back 1

Picornavirus (RNA)

Front 2

Hepatitis B-Family?

Back 2

Hepadnavirus (DNA)

Front 3

Hepatitis C-Family?

Back 3

Flavivirus (RNA)

Front 4

Which types of hepatitis can cause a chronic infection?

Back 4

Hepatitis B & C

Front 5

Hepatitis E-Family?

Back 5

Calicivirus

Front 6

Hepatitis B
Characteristics?
Stability?

Back 6

Hepadnavirus
Fairly stable, resistant to low pH, ether and heat
Can survive in stomach acids

Front 7

Hepatitis B surface antigen (HBsAg)

Back 7

This is present in the blood of those who have Hepatitis B (a marker of Hepatitis B)
However, these are not the cause of transmittance

Front 8

HBV (Hep. B Virus) Replication
Receptors where?

Back 8

Receptors in liver cells and a few other cells.

Front 9

HBV-Replication
Virus uncoats where?

Back 9

In the nucleus, makes an RNA transcript of itself.

Front 10

HBV-Replication-New viruses are released how?

Back 10

Budding

Front 11

HBV-Replication-what enzyme is used?

Back 11

Reverse Transcriptase.

Front 12

HBV-Epidemiology
Who is at risk?

Back 12

Illicit parnteral drug users (sharing needles)
Health care workers with frequent blood contact

Front 13

HBV-Transmission

Back 13

Via blood and blood products
Possibly breast milk
Needles
Sexual contact

Front 14

HBV-Incubation period

Back 14

1-6 months

Front 15

HBV-Acute symptoms

Back 15

Fever, Rash, Jaundice, Dark urine, Malaise, Anorexia, Nausea, Right Upper Quad pain

Front 16

HBV-Resolution

Back 16

90% of cases resolve (cell-mediated immunity)
9% of cases become chronic
1% of cases become Fulminant

Front 17

HBV-Chronic Hepatitis
How long?
What Id's?
Eventual resolution?
Risks?

Back 17

Greater than 6 months
HBsAg id's
About 50% have resolution.
Cirrhotic liver or hepatic cell carcinomas.

Front 18

HBV-Asymptomatic carriers.

Back 18

Some chronic HBV cases result in these.

Front 19

HBV-Chronic Persistent

Back 19

Some chronic HBV cases result in these-develop symptoms outside the liver (polyarteriritis nodosum, glomerulonephritis)

Front 20

HBV-Fulminant Hepatitis

Back 20

Complete destruction of liver cells, despite intervention of cell mediated immune response system.

Front 21

HBV-Chronic Infection
Chronic persistent vs. Chronic active?

Back 21

Persistent is asymptomatic but is still shedding virus.
Active may develop cirrhosis or hepatocellular carcinoma, liver failure, etc.
Chronic symptoms usually more mild than acute.

Front 22

Hepatocellular carcinoma

Back 22

Most common cancer in the world.
More common in males.
Associated with HBV infections

Front 23

What does the presence of HBsAg in the blood indicate?

Back 23

The continual replication of the HBV virus.

Front 24

HBV-anti-HBsAg when do we see them?

Back 24

We won't see HBsAg and anti-HBsAg at high levels at the same time.

Front 25

HBV-Vaccination

Back 25

Introduced the gene into a plasmid that presents the surface antigen without using the virus itself.
85-87% develop antibodies after first dose.
95% after 2nd dose.

Front 26

HAV-Characteristics?

Back 26

Picornavirus
Enterovirus (can grow at core body temp.)
No envelope
Icosahedral capsid

Front 27

HAV-Stability?

Back 27

Extremely stable
Tough receptors
-20 deg. C to -70 deg. for years (ice cubes)
50 degrees C for long time
Stable in formalin for 3 days
Stable in chlorine for 30 minutes (HIV sensitive to chlorine)
Must be boiled for 5 minutes

Front 28

HAV-Replication
Where does it replicate?

Back 28

Cytoplasm
Only infects liver cells

Front 29

HAV-Epidemiology
Transmission?

Back 29

Oral-fecal route (bad lettuce)
Seldom in the blood
Sexual contact
Shellfish (in dirty seawater)

Front 30

HAV-Pathogenesis

Back 30

Oral acquisition
Crosses intestines
Viremia in blood
To Liver
To Bile
To Stool

Front 31

HAV-Incubation period

Back 31

15 days, much shorter than HBV

Front 32

HAV-Acute symptoms

Back 32

Come on abruptly (unlike HBV)

Front 33

HAV-Virus detectable where?

Back 33

In liver, feces, blood, serum enzymes

Front 34

HAV-Fulminant

Back 34

1-3 cases per 1000
A severe, unarrested infection

Front 35

HAV-Diagnosis

Back 35

Shell fish exposure
Less severe symptoms than HBV
IgM in blood against HAV

Front 36

HCV-Characteristics

Back 36

Flavivirus
Enveloped
Icosahedral capsid
90% of nonHAV, nonHBV are HCV

Front 37

HCV-Transmission

Back 37

Primarily through needles and sexual contact
Transfusions used to be a concern

Front 38

HCV-Incubation period

Back 38

4 days to 4 months

Front 39

HCV-Acute cases

Back 39

70-75% are subclinical
Those that are diagnosed often become chronic infections-70% of infected deal with some form of liver disease

Front 40

HCV-Fatalities?
Transplants?

Back 40

8,000-10,000 per year
Leading cause for liver transplants (new livers can be infected too)

Front 41

HCV-Diagnosis

Back 41

Rule out HAV and HBV
Test for HCV with ELISA test

Front 42

HCV-Treatment

Back 42

Interferon & Ribavirin
Liver Transplant
No vaccine

Front 43

HDV(Delta Agent)-Characteristics

Back 43

Defective satellite virus
Doesn't replicate by itself
Liver cells must first be infected by HBV (Dependovirus)

Front 44

HDV-Coinfection

Back 44

HBV & HDV at the same time

Front 45

HDV-Superinfection

Back 45

First chronic HBV, then infection with the delta agent

Front 46

HEV-Characteristics

Back 46

Calicivirus
No envelope
ssRNA
Icosahedral capsid
Id'd by exclusion of other Hep viruses
Enterically transmitted

Front 47

HEV-Transmission

Back 47

Oral fecal route (bad water)
See outbreaks associated with poor wells, ponds, etc.

Front 48

HEV-Course of infection
Incubation period length?
Chronic?

Back 48

Similar to HAV
Incub. period is 2-9 weeks
No chronic form

Front 49

HAV-Treatment

Back 49

Immune serum Ig during incubation 80-90% effective

Front 50

HEV-Fatalities?

Back 50

Fatalities sim. to HAV (unique risk to pregnant women in 3rd trimester-Liver is already at top capacity)