HBV_High_Yield_Flashcards_Part2
What is the role of HBsAg in vaccination and immunity?
HBsAg is the main target for the HBV vaccine and induces immunity by triggering anti-HBs antibody production.
What is the significance of HBV DNA polymerase?
HBV DNA polymerase has reverse transcriptase activity, essential for replication and formation of cccDNA.
How does HBV resist environmental stress (e.g., heat, disinfectants)?
HBV resists drying, heat, and disinfectants by being enveloped and stable under various environmental conditions.
What is the mechanism of HBV replication in hepatocytes?
HBV enters hepatocytes, forms cccDNA in the nucleus, transcribes mRNA, translates proteins, and assembles virions in the cytoplasm.
What are the clinical stages of HBV infection?
Incubation, prodrome (non-specific symptoms), acute hepatitis (jaundice, elevated ALT), convalescence, and chronicity (if applicable).
What are the key characteristics of chronic HBV infection?
Chronic HBV infection involves persistence of HBsAg for >6 months, with a risk of cirrhosis and hepatocellular carcinoma.
How does sodium hypochlorite (0.5%) inactivate HBV?
Sodium hypochlorite destroys HBV antigenicity within 3 minutes at low protein concentrations.
What is the significance of the anti-HBe antibody?
Anti-HBe antibody indicates reduced infectivity and suppressed viral replication in chronic HBV cases.
What are the indications for HBV immunoglobulin (HBIG)?
HBIG is indicated for neonates born to HBV-positive mothers and post-exposure prophylaxis in non-immune individuals.
What are the ‘sub-forms’ of HBV observed in infected patients?
HBV sub-forms include complete virions (Dane particles) and incomplete particles with HBsAg but no DNA.
