Hello and welcome to HCM!
Your question it is very interesting! I will try to summarize briefly the answer: of all persons contacting
hepatitis B virus, 80-85% of them get healed spontaneously (the body's immune system reacts properly and the infection is eradicated), in 10-15% of cases the infection becomes chronic (asymptomatic carriers, resulting positive for the HBsAg surface antigen) and of the later, around 5% might end in
cirrhosis or
liver cancer. The asymptomatic carriers do not benefit much from being vaccinated against hepatitis B. Their treatment with
interferon only in some cases will cause total remission, but in most cases only will lower slightly the HBsAg titer. In other words, interferon taking does not guarantee results and is expensive. On the other hand, the major part of asymptomatic carriers do not develop signs and symptoms of the disease. In this context, since
vaccine is of no use and interferon is expensive and does not guarantee good results (meaning eradication of the antigen is nearly impossible), then the best thing to apply a healthy lifestyle as to not trigger the infection to get "active", by avoiding for example extensive use of alcohol etc.
Hope this answer helped you!