الفهرس 
Hepatitis B
Nature of HBV VaccineOnly 14 pages are availabe for public view
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Abstract
SUMMARY AND CONCLUSION
Viral hepatitis due to hepatitis B virus(HBV) is a major worldwide public health concern leading to acute and chronic liver disease including cirrhosis and hepatocellular carcinoma.
Immunization is the most effective way to prevent transmission of HBV and hence the development of acute and chronic hepatitis. HBV vaccination has effectively reduced the acute and chronic infection rates as well as related complications in the vaccinated children.
The duration of protection afforded by hepatitis B vaccination is unknown. Anti-HBs is the only easily measurable correlate of vaccine-induced protection.Persons who acieve anti-HBs concentrations of>10 mIU/mL after vaccination have nearly complete protection against both acute and chronic infection, even if anti-HBs concentrations decline subsequently to<10mIUmL with time
The mechanism for continued vaccine-induced protection is thought to be the preservation of immune memory through selective expansion and differentiation of clones of antigen-specific B and T lymphocytes. This has been demonstrated by an anamnestic increase in anti-HBs concentrations after administration of an additional vaccine dose.Although direct measurement of immune memory is not yet possible, these data indicate that a high proportion of vaccines retain immune memory and would have an anti-HBs response upon exposure to HBV.