"Medical science has made such tremendous progress that there is hardly a healthy human left”.

Aldous Huxley

Dear readers!

We present seven studies devoted to perhaps the most important problems within the field of infectious diseases. Four papers concern infection with the human immunodeficiency virus (HIV), two papers analyse hepatitis C (HCV) infection, and one paper addresses non-alcoholic steatohepatitis.

Clinical observations concerning susceptibility to infection as well as HIV infection of varied clinical course were the basis for the research hypothesis on the participation of other factors determining the course of these phenomena. Two papers are devoted to this issue – a review paper and a research paper.

In the natural course of a retroviral infection numerous phenomena are observed. The scope of clinical error makes it necessary to deepen knowledge within practically all fields of medicine. One such problem is tackled in a paper devoted to osteoblast activation disorders in seropositive patients.

HIV infection, despite the broad palette of antiretroviral drugs, is still incurable. This means that the patient who starts antiviral treatment remains on therapy to the end of his/her life. The available drugs in use show undesirable side effects, whereas the development of drug resistance creates numerous obstacles to selecting an appropriate therapeutic combination. Hence there is an intensive search for more effective preparations characterized by a high barrier to resistance. One paper is devoted to this issue.