Viral hepatitis (VH) belongs to the category of infectious diseases of the human body that develop under the influence of viruses, which are diverse in nature, in the ways of their spread and transmission from a patient to a healthy person and have one identical attribute - liver damage. VG is an atroponous infection, which means that their pathogens in natural conditions can only be present in the human body.
In hepatitis of viral origin, pathogens have a selective similarity (tropism) to liver cells. For this reason, the early location of viruses and their replication (reproduction) are manifested mainly in the liver tissue, primarily in liver cells (hepatocytes).
According to the nature and duration of development, hepatitis of viral origin is divided into acute and chronic. The threshold among these two types of disease is relatively taken into account 6 months from the onset of the disease or in certain patients from the onset of infection (if the disease does not develop) and up to 6 months - acute hepatitis B or acute virus carrier, after 6 months - chronic hepatitis or chronic virus carrier. [4; 8].
According to WHO, in different countries of the world more than 2 billion people are infected with viral hepatitis (VH), while about 350 million are carriers of hepatitis B and 500 million of hepatitis C [3; 5].
All known hepatitis viruses are present in the CIS countries. In relation to parenteral infections of viral hepatitis, the CIS countries belong to the region with a moderate incidence rate (35.2 cases per 100,000 people). In Tatarstan, the share of viral hepatitis "B" and "C" in the total number of viral hepatitis is 80%. According to some authors [1], the number of so-called "virus carriers" of infection is growing in our republic, more than 10,000-12,000 primary carriers of hepatitis B and C viruses are registered annually. However, the registered incidence is only a part of the true incidence and only the visible part of the "iceberg". This is due to the fact that most cases of hepatitis B occur outside the scope of medical diagnosis, without jaundice and with minor clinical symptoms. However, the anicteric form of parenteral hepatitis is less dangerous than the icteric form in terms of infection and consequences [10].
Viral hepatitis B and C belong to the group of viral hepatitis with a parenteral transmission mechanism. These pathogenic viruses are taxonomically distinct. Common features are the parenteral transmission mechanism and the obligatory circulation of the virus in the blood [7].
Viral hepatitis B is a strictly parenteral infection caused by the IIBV virus, including CMV; IIBV is highly resistant to cold, heat, chemical and physical attack. It persists for 3 months at room temperature and 25 years in dried plasma; a direct correlation has been demonstrated between IIBV duration and blood levels. [6].
The source of transmission of the virus (HBV) can be all forms of acute and chronic HBV, as well as virus carriers. More important as the main source of infection for the epidemic potential are chronic forms of HBV infection than acute ones. An important role is played by chronic carriers of HbsAg and patients with clinically icteric form of IIBV; the ability of IIBV to persist for a long time, often for life, in the human body is considered as an ecological form of its existence [3; 5].
The most fully studied artificial (artifacial) ways of HBV infection as a result of various parenteral therapeutic, diagnostic, therapeutic and non-medical manipulations, leading to a violation of the integrity of the mucous membranes and skin. The source of infection can be contaminated blood products, medical equipment and instruments, transplanted organs and tissues; transfusion of blood or blood products containing HBV can also cause infection (post-transfusion hepatitis) [8; 11].
In addition to medical procedures, non-medical parenteral injections are of paramount importance in the transmission of IIBV infections. This is especially true of intravenous administration of drugs, which has become widespread in recent years. According to a number of authors [2], it has been shown that in recent years there has been a rapid increase in the number of patients with acute viral hepatitis "B", which is associated with the use of intravenous drugs, and a quantitative increase in the incidence is observed among young men aged 15 to 30 years. . Below is a list of the most common causes of acute viral hepatitis B.
The purpose of this study is to substantiate the functional features of periodontal tissues in chronic hepatitis B, C and mixed infection B + C.
