The HK Red Cross BTS, 15 King's Park Rise, KLN, Hong Kong

With the donor screening procedures and laboratory testing, blood supply nowadays are very safe. However, the risk of transfusion transmitted infection cannot be totally excluded. Besides, there are recently concerns of Hepatitis G virus (HGV) and Creutzfeldt-Jakob disease (CJD) as newly emerged blood-borne infections.

The Hepatitis G virus (HGV) and GB virus C (GBV-C) are different type or sub-type of the same virus. This new Flaviviridae-like agent is found in cases of post-transfusion hepatitis, sporadic hepatitis and fulminant hepatitis. This virus is transmissible through transfusion. It has a worldwide distribution with reported prevalence ranging from 1 to 5% in healthy blood donors. The prevalence is much higher in multiple transfused patients and intravenous drug users. Despite HGV infection may be persistent or chronic, current evidence suggest it does not cause significant liver damage.

CJD is a transmissible degenerative neurological disease with fatal outcome. The causal agent of the disease is thought to be a protein or prion. In animal study, it was shown that the disease can be transmitted by inoculated the blood of infected animal into the brain of an uninfected one. Study has suggested that B cells play a crucial role in the disease dissemination within body. However, to date, there are no case report or epidemiological data suggesting a link between CJD and transfusion. The issue is further complicated with the new variant CJD (nvCJD), which is presumably related to the bovine spongiform encephalopathy or "mad cow disease". While the risk of CJD transmission through transfusion may be theoretical, the same argument may not be applicable to the case of nvCJD.