Immunogenicity of the Hepatitis B Vaccine
More than five decades have passed since the identification of the etiologic agent of hepatitis B and yet this infection is a challenge for public health worldwide. The development and availability of the first hepatitis B vaccines, still in the 1980s, was a milestone for the prevention of the hepatitis B virus, and currently known as the gold standard strategy for the elimination of this infectious disease. In several countries, the introduction of the immunobiological occurred gradually, by age groups and risk groups, and in general, started with newborns and children. This universal immunization strategy has contributed to reducing the incidence and changing the epidemiological profile of HBV worldwide. At the beginning of the 21st century, it was already possible to shift the epidemiological curve of the infection to parasitize with 50 years or more. On the other hand, despite vaccination against hepatitis B being the most assertive tool for the prevention of HBV, the low performance of the vaccine in older groups remains a challenge for public health and the object of this study. To our knowledge, there are no data showing the efficacy of doses of enhanced hepatitis B vaccines for older adults, and the purpose of this study is to investigate and compare the immunogenicity of the hepatitis B vaccine in adult adults aged 50 years and over, using conventional doses (20?g) versus (vs) booster doses.
Start: July 2017