title: [Has the epidemiology of hepatitis C virus infections changed?].
abstract: Chronic hepatitis C is a global health problem. The virus of hepatitis C (HCV) was discovered 15 years ago. According to the Centre for Disease Control in Antlanta the epidemiology of HCV infections has changed in recent years. Simultaneously with a substantial increase in the number of infected i.v. drug addicts (from 35 % to 60 %) and in the number of sexually transmitted infections (from 7 % to 20 %), there has been a drop in the number of patients without a patent risk factor of an HCV infection (from 40 % to 10 %). Localities with a marked increase in local anti-HCV prevalence, significantly higher than the prevalence in blood donors, were identified in Italy, China and Japan. The most probable source of infection in these localities seem to be inadequately sterilized glass injection syringes and needles, which were in use until about 1975. Since adulthood anti-HCV reactivity rises almost linearly with the patients' age: in the group of patients aged 60-69 years it can be as high as 30-40 %. This is usually explained by the use, in previous times, of inadequately sterilized glass syringes and injection needles in i.v. treatment and i.v. blood sampling, by hospital stays exceeding seven days and surgery. The remaining 10 % of as yet unexplained risk factors of HCV infections are most probably the consequence of low socio-economic standards.
  
  
  BACKGROUND
  chronic hepatitis C, epidemiology, risk factors.
authors.affiliation: Department Of Internal Medicine, Faculty Hospital Královské Prague, Czech Republic.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Stránský
authors.forename: Jan
authors.initials: J
authors.lastname: Kyncl
mesh_terms: D016174:Hepacivirus; D006526:Hepatitis C / Q000453:epidemiology; D019698:Hepatitis C, Chronic; D006801:Humans; D015995:Prevalence; D012307:Risk Factors