Current serological tests for hepatitis C are extremely robust and sensitive and are applied in respect of the release of all components at the BTSB. In addition, PCR testing is a further safeguard aimed at detecting hepatitis C during the window period between infection and the production of antibodies which are detected by the standard serological tests. The typical length of the window period without PCR testing is ten-14 weeks. Following introduction of PCR testing, this window period is reduced to approximately two weeks. To date, no donation has tested positive for hepatitis C by the PCR test.
The introduction of PCR testing for hepatitis C is being applied internationally in response to the European committee for proprietary medicinal products (CPMP) requirement that all manufactured blood products released for use within the EU must be derived from plasma pools that have tested negative for hepatitis C by a validated PCR test. This requirement arose from the transmission of hepatitis C associated with HCV screened intravenous immunoglobulin products which involved plasma pools from numerous donors. PCR testing for other blood components is not mandatory. However, in order to further improve safety, PCR testing for the hepatitis C virus is currently performed on all blood donations collected by the Blood Transfusion Service Board. In November 1999, the BTSB entered a contract with the Scottish National Blood Transfusion Service (SNBTS) to carry out PCR testing on its behalf and all donations after that date have been tested.