Epidemiology of blood donors in Japan, positive for hepatitis B virus and hepatitis C virus by nucleic acid amplification testing.
OBJECTIVE
The Japanese Red Cross screens seronegative blood donors by nucleic acid amplification testing (NAT) for hepatitis B, hepatitis C and human immunodeficiency virus-1 markers. NAT-positive donors thus identified seemed to have a different infectious background from serologically positive donors. The purpose of our study was to characterize this background in the hepatitis B virus (HBV) and hepatitis C virus (HCV) NAT-positive donors.


METHODS
Some 328 HBV DNA-positive and 44 HCV RNA-positive donors were detected by NAT testing of seronegative blood donors. These were characterized regarding age, gender and genotype of HBV and HCV.


RESULTS
Those who were HBV NAT-positive were mainly young, in particular teenage girls. In Japan, genotypes C and B have previously been dominant, but recently genotype A has increased, and genotype H was recently detected. In HBV NAT-positive donors, the rate of genotype A was high (12.2%) compared with patients in hospital (1.7-2%). Donors who were HCV NAT-positive were also young, but mostly men in their twenties. The ratio of genotype 1b to 2a or 1b to 2b in HCV NAT-positive donors differed from that of hospitalized patients in Japan. We did not find genotype 1a, which is dominant in the USA.


CONCLUSIONS
The high-risk donors detected by NAT were mainly young, with a different distribution of genotypes from that of hospitalized patients, regarding both HBV and HCV. The rare HBV genotype H has been found for the first time in Japan. The findings reflect the present spread of hepatitis viruses B and C.
Murokawa
H
H
Japanese Red Cross Headquarters, Blood Services Department, Tokyo, Japan.
Yoshikawa
A
A
Ohnuma
H
H
Iwata
A
A
Katoh
N
N
Miyamoto
M
M
Mine
H
H
Emura
H
H
Tadokoro
K
K
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D001782:Blood Donors; D004813:Epidemiology; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification; D006509:Hepatitis B / Q000175:diagnosis / Q000453:epidemiology*; D006515:Hepatitis B virus / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D021141:Nucleic Acid Amplification Techniques; D012737:Sex Factors