Transmission of occult hepatitis B virus by transfusion to adult and pediatric recipients in Taiwan.

Division of Gastroenterology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, 1 Chang-Te Street, Taipei 100, Taiwan.
Journal of Hepatology (Impact Factor: 10.4). 02/2006; 44(1):39-46. DOI: 10.1016/j.jhep.2005.06.016
Source: PubMed

ABSTRACT The infectivity of occult hepatitis B virus (HBV), defined as HBsAg-negative but HBV DNA-positive, after transfusion has been low but not negligible. To address this, we investigated the incidence of post-transfusion HBV infection after receiving screened blood units in Taiwan.
Consecutive HBV-naïve (anti-HBc-negative) recipients with normal ALT were followed for HBV DNA and serologic markers before and after transfusion. Among 4448 blood recipients, 467 (10.5%) were anti-HBc-negative. Post-transfusion 6-month follow-up was completed for 327. We identified 5 (1.5%) who developed hepatitis B viremia 1 week after transfusion. Three were children who later seroconverted to anti-HBc but with normal ALT indicating subclinical acute infection, despite all had anti-HBs from previous vaccination. One had transient transfusion-transmitted HBV without seroconversion to anti-HBc and one possibly had occult HBV infection. Our findings suggested the possibility that occult HBV infection was transmissible by transfusion. The incidence of post-transfusion acute HBV infection was 0.9% (100 per million units) in naïve recipients in Taiwan, a figure 7 approximately 40-fold higher than in developed countries. Moreover, some vaccinated children with anti-HBs were still susceptible.
Therefore, despite active immunization, sensitive screening assays for occult HBV infection such as nucleic acid amplification test could be considered in endemic areas.

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