Long-term immune protection after infant hepatitis B vaccination in children.

Chronic hepatitis B virus (HBV) infection in endemic regions often begins in infancy and persists throughout life. Although anti-HBs antibody levels may decline over time, long-term protection usually remains. The me chanisms underlying this sustained protection are not fully understood. Evidence from studies conducted up to 20 ypost-vaccination indicates that booster doses are unnecessary for immunocompetent individuals who completed the full vaccination series as recommended. Therefore, reviewing HBV vaccination studies in children is crucial to update current knowledge on long-term immunity and evaluate the program's strengths and weaknesses. This literature review analyzed studies published from 2013 to 2023 using PubMed, Google Scholar, ScienceDirect, and Scopus databases with relevant keywords. Selection followed PRISMA guidelines. Twenty-seven studies demonstrated protective effects exceeding 10 y, though antibody levels were lower in adolescents. Booster vaccination during adolescence may be beneficial, especially for those born to HBsAg-positive mothers.