Hepatitis viruses Flashcards

1
Q

What shape is the Hep A virus?

A
  • Spherical
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is the Hep A virus enveloped or non-enveloped and does it consist of RNA or DNA?

A
  • Non-enveloped

- Single stranded RNA genome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Is the Hep A virus stable?

A
  • Yes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How can the Hep A virus be transmitted? (4 points)

A
  • Person to person
  • Food-borne
  • Water-borne
  • Faecal-oral route
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Is the Hep A virus more prevalent in developed or developing countries?

A
  • Developing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the incubation period for the Hep A virus?

A
  • 2-7 weeks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an ‘incubation period’?

A
  • The period between exposure to an infection and the app earace of the first symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does Hep A usually cause on people in relation to infections?

A
  • Usually sub clinical infection - don’t necessarily have any obvious signs or symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the mortality rate of Hep A?

A
  • <0.2%

- People don’t usually die from Hep A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Does Hep A have the ability to cause chronic infections?

A
  • No
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can you diagnose Hep A? (2 points)

A
  • Demonstartion of HAV antigen in faeces

- Serology: detection of IgM anti-HAV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is meant by ACTIVE immunisation?

A
  • Give an antigen and the body produces own antibodies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is meant by PASSIVE immunisation?

A
  • Give a pre-formed antibody
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

A person can be given human normal immunoglobulin for short-term protection against Hep A. How long does this protect you for?

A
  • 4 months
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is in the Vaccine for Hep A? (2 points)

A
  • Formaldehyde-inactivated hep A virus

- Prepared from the GBM or HM 175 strain of hepatitis A virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How long does a single dose of the Hep A vaccine give a person antibodies for?

A
  • 1 year
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

If a person is given the Hep A vaccine and then given a booster dose 6-12 months later, how long should this give them immunity for?

A
  • Immunity for 10 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Hoe many people globally are infected with the Hep B virus?

A
  • 350 million (global problem)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

70% of new cases of Hep B occur among people between the ages of what?

A
  • 15-39

occurs relatively young

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How much more infectious is Hep B than HIV?

A
  • 100 times

only need a small amount of blood to transmit - very infectious

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Is there an effective vaccine available for Hep B?

A
  • Yes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Is there a curative treatment for Hep B?

A
  • No, but new antivirals can suppress the viral loa d
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is meant by ‘viral load’?

A
  • The number of viral particles per ml of blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Is there DNA or RNA in the Hep B virus?

A
  • Partially double stranded DNA virus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is another name for the hepatitis DNA virus?

A
  • Hepadnavirus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How many subtypes of HBV virus exist?

A
  • 8

- You are protected against all of them by the 1 vaccine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is a Dane particle?

A
  • A spherical particle found in the serum in the Hep B that is the virion of the causative double-stranded DNA virus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is another name for the outer coat of a hep B particle?

A
  • Hep B surface antigen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

If a strand of Hep B has the Hep B core antigen what does this mean?

A
  • The likelyhood of transmitting the infection is very high
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the 2 different forms a Hep B virus particle can be?

A
  • Long, cylindrical forms

- Short, circular forms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the most common risk factor of getting infected with the Hep B virus?

A
  • Heterosexual exposure

- A big problem is that a lot of the patients that are infected with the virus will not know

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the 3 main routes of transmission of the HBV virus?

A
  • Bloodborne
  • Sexual
  • Perinatal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What categories of people have a higher risk of transmitting HBV? (7 points)

A
  • IV drug users
  • Sexually active hetero- and homosexuals
  • Children of immigrants from disease-endemic areas
  • Sexual/household contacts of infected people
  • Infants born to infected mothers
  • Healthcare workers
  • Haemodialysis patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the recovery rate of adults in non endemic areas with HBV?

A
  • 95% recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the recovery rate of infants in endemic areas with HBV?

A
  • 5-20% recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

In non endemic countries, what percentage of adults have the inapparent disease of HBV and what percentage has acute hepatitis?

A
  • 80% inapparent disease

- 20% acute hepatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

In endemic countries, do most infants with HBV have an inapparent or chronic hepatitis?

A
  • Mostly inapparent disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

In people with chronic HBV what can this lead to the development in the long term? (2 points)

A
  • Cirrhosis and liver cancer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is the % risk of chronic HBV for neonates?

A

90%-100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the % risk of chronic HBV for children?

A

20%-40%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the % risk of chronic HBV for the HIV positive (immunocompromised)?

A

21%

42
Q

What is the % risk of chronic HBV for adults?

A

<5%

43
Q

If the Hep B surface antigen is positive for more than 6 months, but the person has not developed an antigen to this, what are they?

A
  • A carrier
44
Q

In someone who is making a normal recovery from Hep B. If you look in the blood at an early stage what will be present? (2 points)

A
  • The DNA of the virus

- e antigen

45
Q

As someone is recovering from Hep B what is the last antibody to develop?

A
  • The antibody to the surface protein of Hep B (anti-HBs)
46
Q

In someone who is recovering from Hep B, once the antibody is created to the Hep B e antigen what happens to the patient?

A
  • The patient is now not nearly as infectious
47
Q

What would you give a patient for passive immunisation against the Hep B virus?

A
  • Hep B immunoglobulin

- From pooled plasma

48
Q

What is the main use for passive immunisation against Hep B and when should this be administered by?

A
  • Main use: single acute exposure in non-immune individual

- Administer within 48 hours

49
Q

The HBV vaccine is highly immunogenic. What does this mean?

A
  • It is very able to produce an immune response
50
Q

Is a booster dose required for the HBV vaccine?

A
  • no, no booster dose is required for persons who have responded to the HBV vaccine
51
Q

In active immunisation against HBV what is in the vaccine?

A
  • Hep B surface antigen (HBsAg) absorbed on aluminium hydroxide adjuvant
  • Produced by recombinant DNA technology (perfectly safe)
52
Q

In active immunisation against HBV how effective is the protection?

A
  • Protection is good
53
Q

In active immunisation against HBV how effective is the response against the virus?

A
  • Not always good - need to check antibody levels
54
Q

In active immunisation against HBV how is the vaccine administered?

A
  • IM (intramuscular)
55
Q

In active immunisation against HBV how many doses are required in the treatment and when?

A

Three doses

  • Time zero
  • One month
  • 6 months
56
Q

In active immunisation against HBV what has to be tested post immunisation?

A
  • Test for antibody response 2-4 months after vaccination course complete
57
Q

In active immunisation against HBV do vacc ine responders need any post exposure prophylaxis?

A
  • None required
58
Q

In active immunisation against HBV do vaccine non-responders need and post exposure prophylaxis?

A
  • In the occupational setting, Hep B immune globulin (HBIG) provides an estimated 70%-75% protection from HBV infection
59
Q

The average volume of blood inoculated during a needlestick injury with a 22 gauge needle is 1 microliter. How many infectious doses of HBV are can be contained in this?

A
  • 100 doses

- A non responder to the vaccine that gets a needlestick injury has a 1 in 3 chance of getting hep B

60
Q

What is the goal of therapy of the HBV virus?

A
  • Sustained viral supression
61
Q

What are the 3 types of suppressant agents for the HBV virus?

A

Immunolodulatory agents

  • interferon-alpha
  • Pegylated interferon

Nucleoside analogues

  • Lamivudine
  • Telbivudine
  • Entecavir

Nucleotide analogues

  • Adefovir
  • Tenofovir
  • Don’t cure but are very good suppressants
62
Q

The Hep C virus was discovered in 1989. What was it previously called?

A
  • Non-A, non-B hepatitis
63
Q

What virus is the hep C virus?

A
  • Flavivirus
64
Q

How many genotypes are there for hep C?

A
  • 1-6

- All behave quite differently

65
Q

How many people are affected with Hep C worldwide?

A
  • 200 million people
66
Q

What is the ratio of people who are infected with HIV compared to HCV?

A
  • For every one person infected with HIV, Four are infected with HCV
67
Q

Are there vaccines available for HCV?

A
  • No
68
Q

Are there treatments for HCV?

A
  • Yes, treatments have been improved greatly but they are expensive
69
Q

Is Hep C a DNA virus or an RNA virus?

A
  • Enveloped RNA virus
70
Q

Can the Hep C virus be grown in tissue culture?

A
  • No

- Therefore we rely on serology to make the diagnosis

71
Q

What is the main risk factor of getting HCV in developed countries?

A
  • Intravenous drug use
72
Q

What are the tests available to use to detect HCV virus? (4 points)

A
  • Anti-HCV test
  • HCV-RNA test
  • Viral load/quantitative HCV test
  • Viral genotyping
73
Q

How is the anti-HCV test used to diagnose HCV?

A
  • Detects presence of antibodies - indicates exposure to HCV
74
Q

How is the HCV-RNA test used to diagnose HCV?

A
  • Identifies presence of virus in blood - indicates active infection
75
Q

How is the vial load/ quantitative HCV test used to diagnose HCV?

A
  • Measures the number of viral particles in peripheral blood
  • More virus in the blood the more infectious the person is
76
Q

How is the viral genotyping test used to diagnose HCV?

A
  • Determines the type of HCV present

- Certain genotypes respond better than others to different forms of medication

77
Q

What is the mean incubation period for HCV?

A
  • 6-12 weeks
78
Q

What is a seroconversion period?

A
  • The time period during which a specific antibody develops and becomes detectable in the blood
79
Q

What is the mean seroconversion period for HCV?

A
  • 15 weeks
80
Q

What is an acute infection of HCV like?

A
  • Clinically mild (may be subclinical)

- A high number of these become chronic

81
Q

What is a chronic infection of HCV like?

A
  • High frequency: at least 60% of those infected
  • Most are clinical inapparent infection
  • Most patients unaware of their disease and infectivity
  • Indolent and slowly progressive over 20+ years
  • Progression from milk hepatitis to cirrosis
  • Link with hepatocellular carcinoma
82
Q

From exposure of the HCV virus, what percentage of people will develop the chronic version of the virus?

A
  • 75%
83
Q

Of the people with chronic HCV, what percentage will not be stable and will develop cirrhosis?

A
  • 20%
84
Q

Of the people with chronic HCV that develops into cirrhosis, what percentage will have a slowly progressive infection and what percentage will develop liver failure, HCC, need a transplant or result in death?

A
  • Slowly progressive = 75%

- Liver failure, HCC, transplant, death = 25%

85
Q

As a treatment of chronic Hep C interferon alpha can be combined with other things. What are 2 examples of this?

A
  • Ribavirin (combined with this makes the outcome much better)
  • Plus boceprevir or telaprevir (HCV protease inhibitors) for genotype 1 (combined with this and ribavirin you get much better results)
86
Q

What are 2 examples of second generation protease inhibitors that are used as a newer treatment for chronic Hep C and how do they work?

A
  • Sofosbuvir
  • Ledipasvir
  • These drugs stop new viral particles from being produced
87
Q

Is hep D a DNA virus or an RNA virus?

A
  • RNA virus
88
Q

Why an Hep D only replicate when the Hep B virus is present too?

A
  • Delta agent relies on hep B to produce the outer protein coat for Hep D
  • Could be co-infectant where both infect at the same time OR
  • Super infection where hep B comes first then hep D comes after
89
Q

What percentage of patients infected with hep D recover from a co-infection?

A
  • 90-95%
90
Q

What percentage of patients infected with a hep D co-infection suffer from a fulminant infection (severe or sudden infection)?

A

2%-20%

91
Q

What percentage of patients infected with a hep D co-infection virus develop a chronic infection?

A
  • 2%-7%
92
Q

What percentage of patients infected with a hep D super infection develop fulminant (a severe or rapid onset infection)?

A
  • 10%-20%
93
Q

What percentage of patients infected with a hep D super infection recover?

A
  • 5%-10%
94
Q

What percentage of patients infected with a hep D super infection develop a chronic infection?

A

70%-95%

95
Q

What percentage of patients infected with a hep D super-infection or co-infection that develop a chronic infection will develop cirrhosis?

A

70%-80%

  • This can lead to a hepatocellular carcinoma
96
Q

Is the Hep E virus an RNA or DNA virus?

A
  • Single stranded RNA genome
97
Q

How can the Hep E virus be transmitted

A
  • Faecally contaminated drinking water
98
Q

What is the incubation period for hep E?

A

Incubation period 2-9 weeks

99
Q

What is the mortality rate for pregnant women with Hep E?

A
  • up to 20% mortality
100
Q

Can Hep E develop into a chronic form?

A
  • No