Reactivation of hepatitis B virus infection - an important aspect of multifaceted problem.

In this editorial we comment on the article published in the recent issue of the W. We focus specifically on the problem of occult hepatitis B virus (HBV) infection, that is a result of previous hepatitis B (PHB) and a source for reactivation of HBV. The prevalence of PHB is underestimated due to the lack of population testing programs. However, this condition not only complicate anticancer treatment, but may be responsible for the development of other diseases, like cancer or autoimmune disorders. Here we unveil possible mechanisms responsible for realization of these processes and suggest practical approaches for diagnosis and treatment.