The prevalence of hepatitis B and C markers among narcotic users

611 patients with acute parenteral virus hepatitis (VH) were studied with a view to find out markers indicating the presence of hepatitis B and hepatitis C virus infection (HB, HC, HB + C, HC + HBsAg). Of these, 166 patients (27.2%) systematically used narcotic drugs intravenously. Essential differences between drug users and VH patients without drug addiction were established regarding the distribution of patients by age and sex, the etiological structure and severity of the disease. Thus, in the group of drug users the prevalence of males, young people (15-29 years of age) and the mixed form of hepatitis B + C was noted. In VH patients using drug the disease took a more severe course than in such patients without drug addiction. The highest proportion of intravenously drug users with a severe and moderate course of the disease was found among patients with HB + C and HB.     

The epidemic of human immunodeficiency virus-caused infection among users of psychotropic preparations in Russia

The development of the epidemic of HIV infection among the intravenous injecting users of psychotropic substances in Russia in 1994-1999 is described on the basis of the data provided by territorial centers for the prevention and control of AIDS. In addition, the results of the screening in individual groups of the population of Russia for antibodies to HIV, carried out at the period of 1994 to the first half of 1999, are presented. In 1999 a considerable rise in the number of newly detected cases of HIV infection, mainly among persons injecting psychotropic drugs intravenously for non-medical purposes, was noted. The conclusion was made that the spread of HIV among drug addicts led to its passage to other groups of the population, mainly by heterosexual transmission.     

Immunogenicity of parenterally delivered plant-derived small and medium surface antigens of hepatitis B virus

Key message

Intramuscularly delivered plant-derived M-HBsAg was compared to S-HBsAg, and as a result elicited specific anti-preS2 antibodies and significantly higher titre of anti-HBs antibodies, together with IgG isotype profile indicating some Th1 polarisation, apart from the main Th2 response.

Abstract

HBV prevalence is still threatening, regardless of prevention programmes using vaccines containing S-HBsAg, supplemented by third-generation vaccines, comprising also M- and L-HBsAg. Plant expression systems offer a cost-effective production option of the antigens. Plant-derived S- and M-HBsAg, intramuscularly delivered to mice, elicited anti-HBs antibodies several times higher than high responsiveness threshold titre. M-HBsAg induced stronger response of anti-HBs and also specific anti-preS2 antibodies. IgG isotype profiles indicated mainly Th2 response, yet Th1 polarisation was also pointed out, in some larger extent for M-HBsAg. These results correspond to research on CHO-derived M-HBsAg vs. commercial vaccines based on S-HBsAg and support potency of plant-derived antigens as alternative injection vaccines.

     

Viral sequence evolution in acute hepatitis C virus infection

CD8(+)-T-cell responses play an important role in the containment and clearance of hepatitis C virus (HCV) infection, and an association between viral persistence and development of viral escape mutations has been postulated. While escape from CD8+ -T-cell responses has been identified as a major driving force for the evolution of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV), a broader characterization of this relationship is needed in HCV infection. To determine the extent, kinetics, and driving forces of HCV sequence evolution, we sequenced the entire HCV genome longitudinally in four subjects monitored for up to 30 months after acute infection. For two subjects the transmission sources were also available. Of 53 total non-envelope amino acid substitutions detected, a majority represented forward mutations away from the consensus sequence. In contrast to studies in HIV and SIV, however, only 11% of these were associated with detectable CD8+ T-cell responses. Interestingly, 19% of non-envelope mutations represented changes toward the consensus sequence, suggesting reversion in the absence of immune pressure upon transmission. Notably, the rate of evolution of forward and reverse mutations correlated with the conservation of each residue, which is indicative of structural constraints influencing the kinetics of viral evolution. Finally, the rate of sequence evolution was observed to decline over the course of infection, possibly reflective of diminishing selection pressure by dysfunctional CD8+ T cells. Taken together, these data provide insight into the extent to which HCV is capable of evading early CD8+ T-cell responses and support the hypothesis that dysfunction of CD8+ T cells may be associated with failure to resolve HCV infections.     

Viral hepatitis A and B as a mixed infection in children

Serological examinations of 1,200 children, hospitalized at the viral hepatitis department over a year, for the presence of hepatitis A (HA) and hepatitis B (HB) markers have revealed a 7% incidence rate of mixed HA and HB infections. Three variants of mixed infection have been established (true mixed infection, HA combined with asymptomatic HBsAg carriership, cross superinfection) and the relative significance of each of them has been determined. Mixed infection took an unfavorable course with a tendency to the prolongation of the pathological process eventuating in chronic hepatitis, especially in cases of true mixed infections (15.9%).