HAV

Question 1

What is the HAV?
and to what Family it belongs?

Answer 1

Typical enterovirus
PicoRna Family

Question 2

What type of genome it contain?

Answer 2

Single Stranded RNA

Question 3

Envolpe and shape ?

Answer 3

Non enveloped icosahedral nucleocapsid

Question 4

Where does it replicate?

Answer 4

In the cytoplasm of the cell

Question 5

Serotypes and Antigenic relationship to other hepatitis viruses?

Answer 5

• One serotype
• No Antigenic relationship to other hepatitis viruses

Question 6

Transmission?

Answer 6

Fecal- oral

Question 7

Reservoir?

Answer 7

Human

Question 7

Reservoir?

Answer 7

Human

Question 8

Why quarantine of patients are ineffective?

Answer 8

Because virus appears in feces 2 before symptoms

Question 9

Common source of outbreaks?

Answer 9

Fecally contaminated food or water such as oysters

Question 10

Transmission through blood?

Answer 10

Unlike HBV its rarely transmitted through blood

Question 11

Why its rarely transmitted through blood

Answer 11

Because the level of viremia is low

Question 12

Pathogensis of HAV

Answer 12

Not completely understood its probably replicate in git tract and spread to the liver through blood

Question 13

Hepatocytes are infected but the mechanism is by which cell damage occur is unknown Why is that?

Answer 13

Because it produces no cytopathic effect

Question 14

Then What is likely to causes damage to hepatocytes?

Answer 14

The attack by cytotoxic T cells

Question 15

Does patients heals, can it progress to chronic diseases?

Answer 15

-Infection is cleared and damage is repaired
-No chronic infection ensues

Question 16

What are the immune response and when it is detected?

Answer 16

-IgM Antibody
-at time jaundice appears

Question 17

What happens Next after the appearance of IgM?

Answer 17

Production of IgG after 1 to 3 weeks

Question 18

What Do we use in the laboratory diagnosis of HAV?

Answer 18

The presence of IgM antibody

Question 19

What is the role of IgG antibody ?

Answer 19

Provide Life long protection

Question 20

What are the clinical manifestation of hepatitis regardless of virus?

Answer 20

Fever, anorexia, nausea, vomiting, jaundice, dark urine, pale feces, elevated transaminase levels

Question 21

How long it takes for cases to reaolve spontaneously?

Answer 21

2-4 weeks

Question 22

How long is the incubation period of HAV and HBV?

Answer 22

-(3-4) weeks short (A)
-(10-12) weeks

Question 23

Laboratory diagnosis?

Answer 23

-IgM Antibody is the most important test
-four fold Rise in IgG antibody titer
-Isolation of virus in culture is possible but not available in the clinical laboratory

Question 24

Treatment?

Answer 24

No antiviral therapy is available

Question 25

Prevention

Answer 25

-Active immunization (with vaccine containing inactivated HAV) -passive immunization (with immune serum globulin prior to infection or within 14 days after exposure can prevent or mitigate disease. -proper Hygiene (hands washing after bowel movement and sewage disposal).