Molecular epidemiology of the hepatitis C virus in Western Siberia.

Western Siberia is the region with little information on the prevalence of hepatitis C virus (HCV) infection, genotypic diversity of HCV isolates and risk factors. A molecular epidemiological survey was conducted to clarify these issues. Four groups of volunteers were included in a cross-sectional study (n = 500 in each group): health care workers; daycare patients from a hospital for drug users, daycare patients from an AIDS prevention and control center; and persons admitted to a local general practice clinic for any reason (outpatients). The anti-HCV IgG prevalence was 4.6% in health care workers, 48.0% in a narcological center, 35.8% in AIDS center, and 5.6% in outpatients. HCV RNA was found in 79.3%-86.3% of seropositives. A total of 388 HCV isolates were genotyped by direct sequencing and phylogenetic analysis of the 5'-UTR and NS5B regions of HCV genome. The genotypes distribution was: 1b--50.3%, 2a--4.4%, 2c--0.3%, 3a--44.8%. One isolate (0.3%) could not be typed unambiguously. This genotypic diversity is intermediate between that of European Russia and China. Genotype 1 prevailed in an older age group (75% among 51-60 years old), and genotype 3 was most prevalent in young people (51.4% in 16-20 years old). A statistically significant (P < 0.05) increase in risk was found in intravenous drug users (odds ratio (OR) = 77.5), unemployed persons (OR = 16.3), persons having >4 sexual partners during lifetime (OR = 4.3), and male homosexuals (OR = 6.6).

[Reactogenicity, safety and immunogenicity of a recombinant bivaccine against smallpox and hepatitis B in limited clinical trials]. / Reaktogennost', bezopasnost' i immunogennost' rekombinantnoi bivaktsiny protiv ospy i gepatita B v ogranichennykh klinicheskikh ispytaniiakh.

The reactogenicity of the embryonic live recombinant variola and hepatitis B bivaccine as tablets (Revax-BT) as well as its safety and immunogenicity were evaluated in clinical trials made in volunteers who had previously immunized or not with variola vaccine. A preliminary conclusion was made on a lack of side effects and drug safety in primary vaccination and been revaccination with low and high doses. Primary immunization of volunteers and as bivaccination with high doses stimulated the most pronounced immune response to the vaccine virus versus such effect observed in immunization of volunteers with low vaccine doses. Humoral immune response to HBs was observed in 75% of volunteers of both groups after as bivaccination. Such response was most pronounced in examinees immunized with low vaccine doses versus those who received high bivaccine doses. At the same time, no protective levels of humoral immunity response to HBs Ag were observed in volunteers first vaccinated.

[Occurrence of markers, distribution of genotypes and risk factors for viral hepatitis C among some groups of the population in the Novosibirsk region]. / Vstrechaemost' markerov, raspredelenie genotipov i faktory riska virusnogo gepatita C sredi naseleniia Novosibirskoi oblasti.

The occurrence of markers, genotypic variability of isolates and risk factors for viral hepatitis C (HCV) were studied in 4 groups of residents of the Novosibirsk region (altogether 2,000 persons). Anti-HCV IgG were detected within the range from 4.6% among medical personnel to 48% among the patients of the drug-abuse clinic. The detection rate of HCV RNA in seropositive samples varied from 79.3% to 86.3%. The determination of genotype was carried out for 388 isolates: 1b--50.3%, 2a--4.4%, 2c--0.3%, 3a--44.8%. The highest risk indices with respect to HCV among the residents of the region were linked with the drug use (OR=77.5; p<0.05) as well as with risky behavior and low social status. The elevated numbers of seropositive persons were detected among unemployed (OR=16.3), alcohol abusers (OR=3.9), persons having more than 4 sex partners in their lifetime (OR=4.3) and persons having homosexual contacts (OR=6.6). In some groups blood transfusions also played a definite role in the transmission of HCV. In the analysis, carried out separately for two different genotypes the intravenous use of drugs was perceptibly stronger linked with VHC of genotype 3 (OR=85.5) in comparison with HCV of genotype 1 (OR=49.3) and genotype 2 (OR=41.1). Genotype 1 prevailed in the older age group and genotype 3, among young people.

[Frequency of occurrence of Hepatitis C virus markers and risk factors among hospital personnel in the Novosibirsk region]. / Chastota vstrechaemosti markerov gepatita C i faktory riska u personala bol'nits Novosibirskoi oblasti.

The occurrence of markers, the genotypic variety of isolates and the profile of risk factors with respect to viral hepatitis C among 629 employees of the Regional Clinical Hospital (RCH) in Novosibirsk and 1,020 employees of the Central District Hospital (CDH) in Iskitim were studied in a cross-sectional investigation. The occurrence of hepatitis C virus (HCV) markers was 5.1% in RCH and 2.2% in CDH. Among the risk factors in the population under study were: the medical history of blood transfusions (TF) with 0 TF, anti-HCV = 2.3%; 1 TF, = 5.7% > 1 TF, = 13.5% (p < 0.001); general anesthesia (GA) with < or = 2 GA, anti-HCV = 2.8%; > 2 GA, = 7.8% (p = 0.002); surgical interventions (SU) with 0 SU, = 1.9%; > 0 SU, = 4.3% (p = 0.012); the intravenous use of drugs (OR = 31.8); age (< or = 25 years, anti-HCV IgG = 8.6% > 25 years, = 4.5%); the number of partners of the opposite sex < or = 4 partners, = 2.4%; > 4 partners, = 6.9%; p < 0.001). The probable risk factors at a working place (pricks and cuts, contamination of mucous membranes with blood and other biological fluids, etc.) proved to be faintly related with the status of HBV infection. HBV isolates detected in the examined persons (35 examinees) were distributed by genotypes as follows: 60% of subtype 1b, 28.6% of subtype 2a/2c, 11.4% of subtype 3a. HBV of genotype 1a was not detected in the examined specimens, while the detection rate of genotype 2a/2c was considerably greater than in specimens obtained in the European and Asian parts of Russia (according to the data reported earlier).