title: Change of acute hepatitis B transmission routes in Japan.
abstract: BACKGROUND
  Many years have passed since various prophylactic policies for preventing hepatitis B virus (HBV) transmission were begun. We studied the chronological alterations in HBV infectious routes in patients with acute hepatitis B in the past 27 years.
  
  
  METHODS
  Seventy-two patients with acute HBV infection who were admitted to our hospital during the period 1976 to 2002 were enrolled in this study. This study was divided into two periods (first period, 1976-1990; and second period, 1991-2002), and the HBV infectious routes were studied.
  
  
  RESULTS
  Infectious routes have been changing. Posttransfusion hepatitis was seen only in the first period. In the second period, sexual transmission was the major infectious route (68%), followed by infection at a medical facility or occupational exposure such as needlestick injury (8%).
  
  
  CONCLUSIONS
  Transmission from sexual contact has become the main infectious route of HBV in Japan.
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D018562:Disease Transmission, Infectious / Q000706:statistics & numerical data; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology / Q000635:transmission*; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000706:statistics & numerical data; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012725:Sexual Behavior; D013997:Time Factors; D065227:Transfusion Reaction