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Antibody persistence and immune memory elicited by combined hepatitis A and B vaccination in older adults
Thomas Höhler1, Gudrun Groeger-Bicanic, Bernard Hoet
1Department of Internal Medicine, Johannes Gutenberg-University, Mainz, Germany. thomas.hoehler@prosper-hospital.de
Abstract:
Response to hepatitis A and B vaccines has been reported to decline with age. This open, prospective, single-site study examined the long-term response to the combined hepatitis A/B vaccine Twinrix in 98 primary responders aged 45-67 years. Levels of antibody against hepatitis A virus (HAV) and hepatitis B surface antigen (HBs) were tested 30 months after initial vaccination. At this stage, all participants remained seropositive for anti-HAV and 70% for anti-HBs. A booster vaccination was offered to those who had responded to the first vaccination but then lost protective levels of anti-HBs. An anamnestic response was observed in all cases.
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