[The vaccinal prophylaxis of hepatitis B in Russia--the achievements, problems and outlook]. / Vaktsinoprofilaktika gepatita B v Rossii--dostizheniia, problemy, perspektivy.

Certain specific features of the present epidemic situation with hepatitis B (HB) in Russia were established: significant growth of HB morbidity, starting from 1995; the prevalence of persons aged 15-29 years among HB patients, which was linked with the sharp activation of the sexual route of the transmission of HB virus in recent years; an essential increase in the number of patients having contacted this virus in the process of the intravenous use of drugs. The results of the use of vaccine "Engerix B" among persons belonging to different risk groups were considered (a decrease in HB morbidity among them by 8-19 times was noted), the study demonstrated high immunogenicity anti-HBs antibodies on protective titers were determined in 92.3-95.7% of the vaccinees) and low reactogenicity of the vaccine, as well as stable postvaccinal immunity (5 years after the course of vaccination was completed anti-HBs antibodies were retained in 70.6-74% of the vaccinees). The study showed that only the vaccination of adolescents in combination, in the presence of opportunity, with the immunization of newborn infants and young children in the first year of their life made it possible to produce an essential effect on the activity of the epidemic process. Already in 2 years such organization of work on the prophylaxis of HB in one of the cities of the Sverdlovsk region led to a decrease in HB morbidity by 2.9 times, and among adolescents 9 times.

[The vaccinal prophylaxis of hepatitis B among children born to mothers with persistent HBs-antigenemia]. / Vaktsinoprofilaktika gepatita B sredi detei, rodivshikhsia ot materei s persistiruiushchei HBs-antigenemiei.

In Uzbekistan and Moldova 542 children born of HBsAg carriers were immunized against hepatitis B (with vaccine Engerix B according to the immunization schedule of 4 injections). Anti-HBs antibodies in protective titers were detected by EIA and RIA techniques in 76.7% of children aged 4-5 months after the 3rd injection, in 95.7% of children aged 15-16 months and in 90.0% of children aged 2-2.5 years after the 4th (booster) injection. In the control group (117 nonimmunized children born of HBs carriers) observed during the same period anti-HBs antibodies were detected significantly less frequently (in 7.3%, 11.6% and 12.9% of these children respectively). 1-2 months after the course of immunization was completed 74.1% of the immunized children had high anti-HBs antibody titers (exceeding 1000 IU/ml) with their subsequent decrease by 2-2.5 years of age. In the control group these figures were 27.1% and 29.0% respectively. The index of immunization effectiveness obtained by the comparison of the hepatitis B morbidity rates in both groups was 7.8. No postvaccinal complications were registered.

[Hepatitis B as nosocomial infection (aspects of epidemiology and prevention)]. / Gepatit B kak vnutribol'nichnaia infektsiia (voprosy épidemiologii i profilaktiki).

Hepatitis B (HB) was recorded in 1478 (32.3%) of 4577 patients with acute viral hepatitis in Moscow in 1992. Half (50.6%) the patients were infected with HB virus during therapeutical and diagnostic parenteral interventions in 66.1% of them at hospitals, in 7.5% during transfusions of blood and its components (at hospitals too) in the others via natural routes. The HB morbidity per 100,000 patients treated in some Moscow one-profile hospitals sharply differed (74.2 to 89.6 at one hospitals and 5.9 to 7.6% at others). The high HB morbidity at some Moscow hospitals, the group incidence of the disease were associated with the inadequate sterilization quality of medical and laboratory instruments, with the shortage of expendable instruments. The implementation of a complex of measures at individual hospitals, which were aimed at stopping the artificial HB virus transmission routes resulted in 8.2-11.7%-reductions in HB morbidity rates among the patients treated there. In 1990-1992 the HB morbidity among Moscow medical staff was 3.0-3.5-fold than among adults of the city. Surgeons, reanimatologists, and laboratory personnel more frequently fell ill. HB vaccination should be high-priority among this contingent.

[Risk of infection with hepatitis B and C viruses of medical workers, patients in the hemodialysis ward, and vaccine prophylaxis of hepatitis B infection in these populations]. / Risk infitsirovaniia virusami gepatita B i C meditsinskikh rabotnikov, bol'nykh otdelenii gemodializa i vaktsionoprofilaktika u nikh gepatit B-virusnoi infektsii.

Markers of hepatitis B (HBsAg, anti-HBs) and C (anti-HCV) were detected in 1990-1992 by enzyme immunoassay in 1581 medical workers, 230 last-year students of medical schools, 269 patients hospitalized at hemoperfusion wards, and 701 blood donors. Hepatitis B markers were detected in medical workers two times more frequently than in donors (HBsAg in 4.7 and 2.2% of these, respectively, anti-HBs in 26.2 and 14.0%), and anti-HCV were found almost three times more frequently (in 3.1 and 1.1%, respectively). The incidence of these markers in students of medical schools was the same as in donors. Hepatitis B markers (HBsAg, anti-HBs) were detected in 39.0% of patients of hemoperfusion departments, HBsAg being present in 11.9%, and antiHCV in 25%. A direct relationship was revealed between the incidence of hepatitis B and C markers and duration of treatment at dialysis centers or length of service at therapeutic institutions. Three vaccinations with Engerix B 944 vaccine were administered to 944 medical workers and 162 medical students and four vaccinations in double doses to 40 patients of hemoperfusion centers who had no hepatitis B markers; a month after immunization anti-HBs in protective titers were detected in 91.4, 93.9, and 76.1% of them, respectively, and a year after vaccination these values were 77.2, 82.5, and 53.3%. No cases of hepatitis B, detection of HBsAg, or postvaccination complications in the vaccines were recorded.

[The current problems in the epidemiology and prevention of enteric viral hepatitis in Russia]. / Aktual'nye voprosy épidemiologii i profilaktiki énterial'nykh virusnykh gepatitov v Rossii.

The presence of great differences in the activity of the epidemic process of hepatitis A (HA) in some regions of Russia is shown and the data necessary for establishing the structure of HA foci in groups of children, as well as the proportion of different forms of the disease registered in such foci (the icteric form in 22.7% of patients, the obliterated form in 11.3% of patients, the nonicteric form in 45.5% of patients and the asymptomatic form in 20.5% of patients), are presented. The study revealed that the shedding of HA virus occurred at an early stage (5-10 before a rise in alanine aminotransferase activity in the blood was registered), its excretion lasted for a short time (till jaundice appeared) and no chronic carriership of HA virus was registered. The hospitalization of HA patients after the appearance of jaundice was proved to be unjustified, while measures aimed at the rupture of the fecal-oral mechanism of the transmission of HA virus were shown to have good prospects. The epidemiological features of hepatitis E (HE) are considered. HE cases constituted 2-3.6% of all patients with acute viral hepatitis in Moscow (all these cases were brought from Central Asia). The outbreaks of this infection in the countries of Central Asia were shown to be due to the transmission of the infective agent by the water route. The data on the first results of the use of high-titer specific immunoglobulin for the prophylaxis of HE among 135 pregnant women (only one of these women contacted HE, while in a similar group of women used for control 4 HE cases were registered) are presented.

[Study results and the unresolved problems in the epidemiology and prevention of parenteral viral hepatitis in Russia]. / Itogi izucheniia i nereshennye voprosy épidemiologii i profilatiki parenteral'nykh virusnykh gepatitov v Rossii.

Great differences in the activity of the epidemic process of hepatitis B (HB), the occurrence of HBsAg among the population of different regions of Russia (in the central and northwestern regions among 1.8-2.4% of the population, in Tuva among 9.8% of the population, in Yakutia among 11.6% of the population) and considerable differences in the occurrence of HBeAg among HBsAg carriers in these regions (antibodies to delta virus have been detected in 1.3-5.5% of carriers of this antigen in the European part of Russia and in 21.0% of carriers in Tuva) are shown. The structure of the transmission routes of HB virus, the proportion of the artificial and natural routes of its transmission are analyzed. The data on the frequency of cases of perinatal and intrafamily HB virus infection in regions with different activity of the epidemic process, as well as the data on effectiveness of measures for the prevention of posttransfusion HB and parenteral infection during therapeutic and diagnostic interventions, are given. The results of the use of Engerix B vaccine among 2,500 persons belonging to groups of risk are presented. The proportion of hepatitis C (HC) cases among patients with different kinds of acute and chronic viral hepatitis among the population of different regions and the occurrence of anti-HC antibodies among the population of different regions of Russia (in Moscow and St. Petersburg among 1.1-1.2% of the population, in North Caucasia among 4.5% of the population), as well as in high risk groups (3.1% among medical personnel, 19.4% among drug addicts, 25% among patients of hemodialysis wards, ets), are considered. The structure of transmission routes of HC virus is analyzed, the possible measures for the prophylaxis of HC virus infection are considered.

[The detection of antibodies to the hepatitis C virus and to HBsAg in donors with viral hepatitis and cancerous diseases in the Republic of Moldova]. / Vyiavlenie antitel k virusu gepatita C i HBsAg u donorov, bol'nykh virusnymi gepatitami i onkologicheskimi zabolevaniiami, v Respublike Moldova.

Large-scale and uneven distribution of hepatitis C and B (HC and HB) among free blood donors of different regions of the Moldova Republic was established. The rate of detection of anti-HCV (South 6.2%, North 3.6%) correlated with that of HBsAg detection (south 12.5%, north 4.5%). A great role of HCV in the etiology of acute (among them posttransfusion) hepatitis and chronic hepatitis was demonstrated. A significant frequency of detection of anti-HCV (15%) in children treated in oncohematology wards and receiving multiple hemotransfusions as well as the detected cases of acute posttransfusion HC attest to active realization of this virus transmission in the transfusions of blood and/or its components. The necessity of urgent introduction into the Blood Transfusion Service of the republic of the examination of blood donors for HBsAg, alongside with their examination for the presence of anti-HCV and vaccination prophylaxis of HB in high risk groups is substantiated.

[Perinatal infection with hepatitis B virus and the problem of its specific prevention]. / Perinatal'noe infitsirovanie detei virusom gepatita B i voprosy spetsificheskoi profilaktiki.

The incidence of HBs- and HBe-antigens detection in future mothers was studied in Moscow, Uzbekistan, and Moldavia, and the incidence of hepatitis B (HB) virus transmission from mothers with persisting HBs-antigenemia to their offspring. In reverse passive hemagglutination test, HBsAg was detected in 1.1% of pregnancies in Moscow, in 6.3% of pregnancies in Uzbekistan, and in 5.4% of pregnancies in Moldavia. In these regions, immunofluorescence revealed HBe-antigen in HBsAg carriers in 5.2, 13.9, and 16.3%, respectively. Perinatal infection with HB virus was found in 26.1% of births to HBsAg carriers in Moscow and in 40% in Uzbekistan and Moldavia; in the latter two regions 16.0% and 13.3% of these births were found to become chronic carriers of HBsAg. In the presence of persistence of HBeAg in HSsAg carriers, from 89 to 100% births to these mothers showed the development of durable HBs-antigenemia, while in the presence of anti-HBe such outcome was noted in only 3%. Specific anti-HBs-immunoglobulin administered to infants born to HBsAg carriers exerted a protective effect by reducing the HB virus infection rate in the first 6 months of life, but failed to prevent completely the development of HB virus infection. The necessity of a wide-scale vaccination against HB in order to prevent HB virus infection of neonates is emphasized.

[The epidemiological problems of viral non-A, non-B hepatitis with a fecal-oral mechanism of infection transmission]. / Voprosy épidemiologii virusnogo gepatita ni A ni B s fekal'no-oral'nym mekhanizmom peredachi infektsii.

The results of the study of the epidemiological regularities of viral hepatitis non-A, non-B with the fecal-oral mechanism of the transfer of infection in one of the regions of the Turkmenian SSR are presented. These results have been confirmed by serological and virological laboratory methods. The territories, groups of the population (age groups) and the time of the maximum epidemic risk of infection have been determined. The main (primary) role of the water route (polluted ground water) in the spread of this infection has been proved.

[Epidemiological characteristics of non-A, non-B viral hepatitis with a fecal-oral transmission mechanism]. / Epidemiologicheskie osobennosti virusnogo gepatita ni A ni B s fekal'no-oral'nym mekhanizmom peredachi.

The analysis of verified cases of non-A-non-B hepatitis with the fecal-oral mode of transmission which had occurred in one of the districts of the Turkmen SSR, 1984-1985, revealed a this infection: an explosive nature of the incidence, number of epidemiological characteristics of this infection: an explosive nature of the incidence, even distribution in the territory of the district and within one residential area, predominant affection of 15-29-year-old subjects, high mortality among hepatitis-affected pregnant women, insignificant number of secondary cases in the families of index cases. The occurrence of these non-A-non-B hepatitis cases was associated with water. The results of virological and serological studies ruled out the role of hepatitis A and B viruses in the etiology of the acute hepatitis cases occurring in the area. Anti-hepatitis A IgM was detected in the blood in only 3% of the patients in 1984 and in 2% in 1985, exclusively in young patients, and HBsAg in 11% and 9%, respectively. Immune electron microscopy revealed virus-like particles 27-30 nm in diameter in fecal extracts from the patients. The antigen of non-A-non-B hepatitis virus was detected in the first days of the jaundice period in feces of 14% of the patients in 1984 and in 11% in 1985 by an enzyme-immunoassay using a test developed at the Institute of Virology of the USSR Academy of Medical Sciences.

[Clinico-epidemiological characteristics and diagnosis of viral non-A, non-B hepatitis with fecal and oral mechanisms of transmission of the infection]. / Kliniko-épidemiologicheskie osobennosti i diagnostika virusnogo gepatita ni A, ni B s fekal'no-oral'nym mekhanizmom peredachi infektsii.

The paper deals with observations of the patients with non-A-non-B hepatitis (NANBH) transmitted by the fecal-oral mode. The disease was diagnosed by ruling out other similar diseases of the liver, primarily viral A (HA) and B (HB) hepatitides, using clinical and epidemiological data and highly sensitive methods of laboratory diagnosis of HA and HB. Cases of NANBH occurred in one of Central Asia regions in the period of the usual seasonal rise of incidence. The disease was more frequent in adults, running a mild course in most patients, although there were also severe forms with fatal outcomes observed only in pregnant women in the second half of pregnancy. The lethality among the pregnant women was 15.7%. Immune electron microscopy of fecal specimens collected from the patients in the early days of jaundice revealed virus-like particles of 27-30 nm in diameter, morphologically similar to HA virus but forming no immune complexes upon treatment with blood sera containing antibody to HA virus antigen.

[Immunological and epidemiological effectiveness of the HEVAC B vaccine against hepatitis B in a group at enhanced risk of infection]. / Izuchenie immunologicheskoi i épidemiologicheskoi éffektivnosti vaktsiny HEVAC B protiv gepatita B v gruppe povyshennogo riska zarazheniia.

The immunological and epidemiological effectiveness of HEVAC B vaccine against hepatitis B (Pasteur Institute, France) was studied in 215 medical workers of Moscow who had contacts with the blood or preparations thereof. A control group consisted of 155 medical workers. The groups were formed randomly but both included the subjects without HBsAg and anti-HBs. The HEVAC B vaccine was found to be characterized by high immunologic efficacy. Administration of the vaccine induced seroconversion after the 1st, 2nd, and 3rd vaccinations in 36.3%, 77.2%, and 93.9% vaccinees, respectively. In the course of immunization, a marked rise of specific antibody levels was observed. Among the vaccinees no cases of hepatitis B with jaundice were recorded, while in the control group there were 2 cases (1.3%). The vaccine has a low reactogenicity and is safe for use.

[Risk of hepatitis infection of the recipients of blood from donors with HBs-antigenemia]. / Risk zabolevaniia gepatitom retsipientov krovi donorov s HBs-antigenemiei.

Observations were made on 100 recipients of blood from 40 donors with HBs-antigenemia and 106 recipients of the control group, who had received 570 ampules of blood from 491 donors, and 499 ampules from 400 donors, respectively. The incidence of post-transfusion serum hepatitis in the icteric forms was 12.7% and 1.9%, respectively (P less than 0.002), varying between 8.9% and 22.2% in the experimental subgroups, and decreasing with the increase of the total number of blood transfusions received by the subjects. The source of infection proved to be 0.5% of the donors in the control group, and 2.65% in the experimental group (P less than 0.01), or 17.9-33.3%, of donors with HBs-antigenemia. With the sufficient number of recipients traced to each donor, all donors with HBs-antigenemia were found to be the sources of infection. It means that HBs-antigenemia may be regarded as the indication of the presence of the complete (infective) hepatitis virus B in the body.