Time trends of HBsAg prevalence among blood donors in Fukuoka, Japan.
We examined time trends of the prevalence of hepatitis B surface antigen (HBsAg) among blood donors at the Fukuoka Red Cross Blood Center, Japan, during 1977-88. As was expected, a marked but artificial decrease in the HBsAg prevalence attributable to a notification program was detected. The seropositivities among males were uniformly higher than those among females. About 1% absolute rate decrease (approximately 50% relative rate reduction) was found among young donors aged 16-19 in seven years before the notification schedule. An age effect closely related to self-selection due to chronic hepatitis B virus (HBV) infection was demonstrated in the declining trends according to the advance of age. A remarkable birth cohort effect was also observed for both sexes. These data undoubtedly indicate that there were medical/iatrogenic factors as well as natural (sanitary/socioeconomic/nutritional) factors causing the reduction of chronic HBV infection.
Maeda
Y
Y
Fukuoka Red Cross Blood Center, Japan.
Matsushita
K
K
Tokudome
S
S
Tsuji
N
N
Ikeda
M
M
Fujii
M
M
D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D016358:Contact Tracing; D005260:Female; D006509:Hepatitis B / Q000097:blood / Q000453:epidemiology*; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013997:Time Factors
D006514:Hepatitis B Surface Antigens