HBV_High_Yield_Flashcards

Question 1

What is the family and genome type of Hepatitis B Virus (HBV)?

Answer 1

Family: Hepadnaviridae. Genome: Circular double-stranded DNA (3.2 kb).

Question 2

What is the structure of HBV?

Answer 2

Enveloped virus with icosahedral shape, contains DNA polymerase with reverse transcriptase activity.

Question 3

What are the key antigens of HBV and their clinical importance?

Answer 3

HBsAg: Indicates acute or chronic infection. HBeAg: High infectivity. HBcAg: Found only in hepatocyte nuclei.

Question 4

What does HBsAg (surface antigen) indicate?

Answer 4

HBsAg indicates acute infection. If present for >6 months, it suggests chronicity.

Question 5

What does HBeAg (envelope antigen) indicate?

Answer 5

HBeAg is a marker of high infectivity and active replication.

Question 6

What does HBcAg (core antigen) indicate?

Answer 6

HBcAg is found only inside hepatocyte nuclei and is not detectable in blood.

Question 7

What does HBcAb IgM indicate?

Answer 7

HBcAb IgM indicates acute infection.

Question 8

What does HBcAb IgG indicate?

Answer 8

HBcAb IgG indicates past or chronic infection.

Question 9

What does HBeAb indicate?

Answer 9

HBeAb suggests low infectivity and reduced viral replication.

Question 10

What does HBsAb indicate?

Answer 10

HBsAb indicates immunity (recovery or vaccination).

Question 11

What is the ‘window period’ in HBV infection?

Answer 11

During the window period, HBsAg and HBsAb are undetectable; only HBeAb & IgM is present.

Question 12

What are the modes of transmission for HBV?

Answer 12

Blood and body fluids, sexual transmission, vertical transmission (mother to fetus), needle sharing, inadequate sterilization.

Question 13

What is the standard treatment for HBV?

Answer 13

Pegylated interferon for 6–12 months, especially in HBeAg-positive patients.

Question 14

Which antiviral drugs are used for HBV?

Answer 14

Lamivudine, Adefovir, Telbivudine.

Question 15

What is the vaccination schedule for HBV?

Answer 15

Recombinant DNA vaccine given at birth, 2, 4, and 6 months; high-risk groups receive 3 doses.

Question 16

What measures are used to prevent vertical transmission of HBV?

Answer 16

Administer HBIG (specific immunoglobulin) to neonates born to HBV-positive mothers, followed by vaccination.

Question 17

What percentage of HBV cases progress to mild symptoms, jaundice, or chronicity?

Answer 17

70% develop mild symptoms, 25% develop jaundice, and 5% progress to chronic hepatitis.

Question 18

What diagnostic tests are used for HBV?

Answer 18

ELISA detects antigens (HBsAg, HBeAg) and antibodies (HBcAb, HBsAb).

Question 19

What is the role of PCR in HBV diagnosis?

Answer 19

PCR detects HBV DNA and confirms active replication.

Question 20

How stable is HBV in the environment?

Answer 20

Stable at -20°C for over 20 years, at 25°C for 1 week, and at 37°C for 60 minutes.

Question 21

How can HBV be inactivated?

Answer 21

Inactivated by boiling (100°C for 1 minute), sodium hypochlorite (0.5%), or heat at 60°C for 10 hours.

Question 22

What are the main phases of HBV infection markers?

Answer 22

Acute phase: HBsAg, HBeAg, and HBcAb IgM are present. Chronicity: HBsAg and HBcAb IgG remain.