VIRAL HEPATITIS C: EVOLUTION OF THE EPIDEMIOLOGIC PROCESS, EVOLUTION OF THE VIRUS

Abstract

Periodization of the evolution of epidemic process of hepatitis C is given based on the results of phylodynamic, phylogeographic, historic and demographic studies: invasion of the virus into European and North American population in 1700 - 1850; primary activation of the epidemic process in the years of the World War 1; expansive growth of prevalence in 40 - 60s of the 20th century due to mass parenteral interventions; new rise due to heroine drug abuse in 60 - 80s of the 20th century; manifold reduction of incidence of acute hepatitis C in industrial countries for the last 10 - 15 years as a result of general medical measures of prevention of hemocontact infections. A problem of possibility of hepatitis C management and necessity of evaluation of effectiveness of existing prophylaxis measures involving quantitative analytical methods of epidemiology is discussed. Data from phylogenetic studies on stages of hepatitis C virus evolution (HCV) are provided: division of its root genetic lineage with homologous hepaciviruses of animals 985 - 2013 years ago; division ofHCV into genotypes 500 - 2000 years ago; division ofgenotypes into subtypes 70 - 300 years ago. Contribution of mutations and genetic recombinations into HCV evolution is discussed. Genotyping is stated as an inefficient approach for determination of pathogenicity determinants, immune evasion, non-responsiveness to therapy, as well as search for predictors of infection outcome. A necessity of genomic approach for these aims is justified, as well as for risk monitoring, ensuing from continuing evolution and biodiversity of HCV and other hepaciviruses.

Keywords

• hepatitis c virus
• taxonomy
• epidemic process
• evolution