RESUMEN
Hepatitis delta (HD) is characterized by rapid progression to fibrosis, and development of hepatocellular carcinoma, and a high mortality rate. The article presents data on the epidemiology, diagnosis, treatment of HD. The views of the epidemiological, clinical and virological characteristics of HD-infection among population of the Russian Federation (RF) are limited due to absence of official HD registration and detection of antibodies to the HD virus (anti-HDV) in HBsAg-positive individuals. However, some areas of the country are characterized by a high HDV circulation (Republic Tyva (RT) - 46,5%, Republic Sakha (Yakutia) - 12,5%) according to our studies conducted in 6 regions of Russia. Clinical-epidemiological situation of HDV infection in RT can be considered as a model to create a program of optimize diagnosis, prevention and treatment of HDV-infection in the Russian Federation.