hbv screening further improvement of blood safety based on the knowledge deduced from the results on...

4
HBV screening Further improvement of blood safety based on the knowledge deduced from the results on analysis of the donor’s sera positive for HBV DNA by NAT as well as the results of experimental HBV infection to Chimpanzees Hiroshi YOSHIZAWA 1 MD Junko TANAKA 1 PhD Keiko KATAYAMA 1 MD Hisao YUGI 2 PhD Tetsushi TOMOGURI 3 PhD 1. Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan 2. Division of NAT, Japanese Red Cross Association, Tokyo, Japan 3. Primate Center, Sanwa Kagak, Ltd., Kumamoto, Japan

Upload: neil-barnett

Post on 04-Jan-2016

216 views

Category:

Documents


2 download

TRANSCRIPT

Page 1: HBV screening Further improvement of blood safety based on the knowledge deduced from the results on analysis of the donor’s sera positive for HBV DNA

HBV screening

Further improvement of blood safety

based on the knowledge deduced from the resultson analysis of the donor’s sera positive for HBV DNA by NAT

as well as the results of experimental HBV infection to Chimpanzees

Hiroshi YOSHIZAWA1 MD

Junko TANAKA 1 PhD

Keiko KATAYAMA1 MD

Hisao YUGI 2 PhD

Tetsushi TOMOGURI 3 PhD

1. Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan

2. Division of NAT, Japanese Red Cross Association,Tokyo, Japan

3. Primate Center, Sanwa Kagak, Ltd., Kumamoto, Japan

Page 2: HBV screening Further improvement of blood safety based on the knowledge deduced from the results on analysis of the donor’s sera positive for HBV DNA

● Importance of HBV DNA Testing

● Natural Course of Persistent HBV infection- typical/ or classical pattern of HBV carrier state -

● Natural Course of Acute HBV Infectionclinically : anamnestic infectionvirologically : (atypical) HBV carrier state

● Characteristics of Acute HBV InfectionLate phase of Infection

● Relationship between quantity of HBV DNA and titer of anti HBc

Page 3: HBV screening Further improvement of blood safety based on the knowledge deduced from the results on analysis of the donor’s sera positive for HBV DNA

● Detection of HBsAg by highly sensitive immunoassay method (PRISM) in 268 early phase of HBV infected blood donors : both negative for HBsAg (by R-PHA method) and anti HBc ( by CLIA method)

● Experimental HBV infection using model animal (Chimpanzees)

● Results of the experiment- 10 copies of HBV DNA can transmit HBV to Chimpanzees -

● Doubling time and log time of HBV DNA in the peripheral blood of HBV (genotype A, early phase) infected Chimpanzees

● Characteristics of Acute HBV InfectionEarly phase of Infection

Page 4: HBV screening Further improvement of blood safety based on the knowledge deduced from the results on analysis of the donor’s sera positive for HBV DNA

Importance of HBV DNA testing for Blood Safety

For late stage of HBV infectionStrategy should be different in hyper-endemic area and l

ow-endemic area of HBV infection.

For early stage of HBV infectionGenerally saying, it is almost impossible to achieve 10

0% of blood safety by HBV DNA testing solely both in hyper-endemic area and low-endemic area.

Other strategy such as social edecation to donors should be considered.

conclusion