Abstract:Abstract. The prevalence of HBV infection is estimated by the frequency of occurrence of HBsAg and varies depending on the geographic region. Chronic infection is characterized by a stable presence of HBsAg for 6 months, with the exception of the occult form of the disease, characterized by the absence of HBsAg, an extremely low level of HBV DNA in the blood serum. The problem of identifying occult HBV (ocHBV) is especially relevant because of the development of transplantology and transfusiology. However, ser… Show more