Microbio Week 10 - Hepatitis Viruses (Exam 3) Flashcards
All infections with Hepatitis viruses A to E are __________ infections
systemic
T/F: The symptoms of acute viral hepatitis are different for all the viruses. You can easily tell which virus caused your symptoms without doing either serology or nucleic acid testing
FALSE, symptoms of acute viral hepatitis are SIMILAR for all the viruses. You CANNOT tell which virus caused your symptoms without doing either serology or nucleic acid testing
Describe Hep viruses A-E
A - acute
B - bloodborne
C - chronic
D - defective
E - enteric, expecting
What family is Hep A in?
Picornavirus
What is the primary route for Hep A?
Fecal-oral
Are all Hep A infections acute or chronic?
Acute
T/F: Once infected with Hep A, there is protection for life against reinfection
True
T/F: Washing hands is better than alcohol-based hand sanitizers
True
The Hep A virus is shed in feces _________ before symptoms and during symptoms
1-2 weeks
You are most likely to get _________ if infected with Hep A as an older child/adult
jaundice
What vaccine is available for Hep A?
Inactivated
What are the post-exposure prophylaxis recommendations for Hep A?
- Vaccine within 2 weeks
- Vaccine + IgG at distal sites if older, immunocompromised, or have liver damage
- IgG only if younger than 1 or allergic to vaccine
What family is Hep E virus in?
Hepevirus
What are the primary routes of Hep E infection?
Fecal-oral
Contaminated drinking water
What is a significant source of hepatitis outbreaks worldwide, but not in the US?
Hep E
Are all Hep E infections acute or chronic?
Acute
There is a high fatality rate in what type of people infected with Hep E?
Pregnant, especially in 3rd trimester
Is there a vaccine for Hep E?
No
What family is Hep C in?
Flavivirus
How is Hep C transmitted?
Blood
What is the primary spread of Hep C?
Shared needles
Sex
Vertical transmission (mother to baby)
What is the risk of Hep C infection from needlestick exposure?
0.2%
(used to be 3%)
Are Hep C infections acute or chronic?
Chronic
In Hep C infection, it takes several years to develop what?
Cirrhosis/liver disease
What is one of the top reasons for liver transplants?
Hep C
What cells cause liver damage in Hep C infections by killing infected cells?
CD8+ CTLs
Is there a vaccine for Hep C?
No
What should you do if you are infected with Hep C?
Start antivirals immediately
What do the Hep C antivirals target?
- Viral protease
- Viral polymerase
- Viral protein NSSA
What Hep C antiviral target stops replication after translation of +ssRNA because it can’t cleave the polyprotein?
Viral protease
What Hep C antiviral target stops the virus from replicating the viral genome?
Viral polymerase
What Hep C antiviral target stops genome replication and assembly?
Viral protein NSSA
Depending on the genotype of Hep C, the cure rate when treated with antivirals is over ___%, but a person can become re-infected if re-exposed
90
What family is Hep B virus in?
Hepadnavirus
What does Hep B replicate through?
An RNA intermediate
What does Hep B have?
Reverse transcriptase
How is Hep B and D transmitted?
Blood
What is the primary spread of Hep B and D?
Needles
Sex
Pregnancy/delivery
How long can Hep B last on a surface, even tho it is an enveloped virus?
7 days
If a needle stick with a known Hep B virus positive source occurs, how many people will become infected if not protected by vaccine?
30%
If infected with Hep B as an adult, there is a ___% chance that you will be chronically infected
5
If infected with Hep B as infant through vertical transmission, there is a ____% chance of becoming chronically infected
90
The presence of what means you are actively infected with Hep B and can infect other people?
HBsAg
What is the Hep B surface antigen?
HBsAg
The presence of what means you have a high level of Hep B virus in your blood and are very infectious?
HBeAg
What is the Hep B e antigen?
HBeAg
What vaccine is available for Hep B?
Subunit
What does the Hep B subunit vaccine contain?
HBsAg
What is the treatment for Hep B are an exposure?
- Vaccine + HBIG if unvaccinated, have low titers, or baby born to infected mother
- 2 shots of HBIG 1 month apart if vaccine non-responder
What is the target of Hep B antivirals?
Reverse transcriptase
What is the treatment for Hep B?
Antivirals
T/F: Treatment for Hep B is rarely a cure and once started, usually goes on for life
True
Hep B capsid or core antigen
HBcAg
IgM antibody against Hep B core antigen
Anti-HBc IgM
Indicates the total antibody to HBV core antigen, IgG, and IgM
Anti-HBc
T/F: Anyone who has ever had an HBV infection will have Anti-HBc. This does not tell you if the person is currently infected or not. They could have cleared the infection or been chronically infected. You cannot tell just from the presence of this antibody
True
HBV surface antigen
HBsAg
An antibody to HBV surface antigen
Anti-HBs
HBV E antigen. It is only present when a large amount of virus is present
HBeAg
(e = enormous amounts of virus)
An antibody to the HBe antigen
Anti-HBe
In acute Hep B infections, what antibody will be present?
HBcAg IgM
When is the only time the IgM of the core antigen for Hep B will be present?
Acute infections
Most of the time, in acute Hep B infections, enormous amounts of virus are present, so the ________ and _______ will also be present.
HBsAg and HBeAg
During which time period is the body starting to clear the acute Hep B virus and on the way to resolved infection, and Anti-HBs are being made?
Window period
Can anti-HBs and HBsAg be detected during the window period of acute Hep B infection?
NO, they are binding to eachother in the blood, so lab tests can’t detect them
What can be detected during the window period of acute Hep B infection?
anti-HBc IgM
If ________ is present for greater than 6 months, the person is said to have chronic Hep B
HBsAg
What is always present once a person has been infected with Hep B (it stays for life)?
Anti-HBc
What is present during chronic Hep B infection?
HBsAg
HBeAg
Anti-HBc
What is present in inactive carriers of Hep B?
HBsAg
Anti-HBe
Anti-HBc
What is present in resolved infections of Hep B?
Anti-HBs
Anti-HBe
Anti-HBc
What is present in people immunized from Hep B?
Anti-HBs only
If a person has HBsAg, they are _____________ infectious
potentially
If a person has HBsAg and HBeAg, they are __________ infectious
very
What family is Hep D in?
Deltavirus
What must occur to produce infectious Hep D?
Must infect a cell already infected with Hep B
Can Hep D productively infect a cell on its own?
NO
What does Hep D use to coat its virus?
Uses Hep B’s surface antigen (HBsAg)
Is there a vaccine for Hep D?
Yes, its the Hep B vaccine
T/F: Chronic infection with both HDV and HBV is much worse than infection with HBV alone
True, higher levels of cirrhosis and liver failure occur
What can improve symptoms of Hep D?
Type I interferon
Is Type I interferon a durable cure for most people with Hep D infections?
No
What 2 Hep virus infections can occur at the same time? What is this called?
Hep B and Hep D; co-infection
What are the 2 ways to get infected with Hep D?
Co-infection
Superinfection
In co-infection, what % of people develop chronic infection with Hep B and Hep D?
2%
Which post-exposure prophylaxis is used for co-infection of Hep B and Hep D?
Hep B post-exposure prophylaxis
What is it called when you are already infected with Hep B, and then you get infected with Hep D?
Superinfection
What do you develop if you have superinfection of Hep B and Hep D?
Acute hepatitis
In superinfection, what % of people develop chronic infection with Hep D?
80-90%
Which post-exposure prophylaxis is used for superinfection of Hep B and Hep D?
NONE, since you are already infected with Hep B