Source of the hepatitis “D” causative agent is the person infected with viral hepatitis; and mostly virus is spread by people diseased with a chronic type of hepatitis “B” and at the same time infected with a virus of the hepatitis “D”. It is necessary to notice that all that helps virus “B” spread (uncontrolled sexual contacts, badly disinfected tools and so forth), allows existing and replicating to hepatitis “D” virus.
The incubation interval of the infection has an indefinite term; its synthesizing in an organism may take rather long time, but the virus is capable to show abruptly its activity in case if it gets into the organism of the patient with hepatitis “B”.
The hepatitis “D” is transmitted most often at sexual contact and when using blood derived product. Most of all the surgical patients, tubercular patients and people passing weekly cleaning of their blood by means of hemodialysis catch this virus. Sometimes the virus is met in children that assume its transfer to a fetus during pregnancy. Infection frequency in persons who have free sexual life is especially high; men with homosexual orientation are generally infected.
Susceptibility to the hepatitis “D” virus is very high for people; all people without exception are subjected to it, especially those who are the carriers of hepatitis “B”. Infection gets special probability for those chronic patients whose liver cells have not been noticeably destroyed in the course of virus synthesis in a human body.