Dried blood spot testing for hepatitis C, hepatitis B and HIV

• All Wales/National

Summary

This report outlines the background to, and action required for, the implementation of dried blood spot (DBS) testing of substance misuse service clients across Wales for evidence of exposure to hepatitis C virus (HCV), hepatitis B virus (HBV), and HIV. It is intended as a resource to support substance misuse agencies across Wales to provide DBS for their clients.

Background

Approximately one quarter of drug injectors in Wales are infected with HCV.

Research from South Wales suggests that the majority of HCV positive drug injectors do not know they are infected,¹ much HBV exposure is also likely to be undiagnosed. Recent research suggests that the incidence of HIV is increasing amongst IDUs in the UK.³

Low rates of diagnosis will contribute to the future burden of liver disease in Wales through late identification of viral hepatitis infection manifesting as clinical disease and HIV infection diagnosed at late stages of disease. An opportunity to reduce the further transmission of infection is also missed. There is thus a clinical risk with failing to improve the currently poor rates of diagnosis.

Existing diagnostic testing protocols require the taking of blood samples by venepuncture; this can be problematic amongst drug injectors who often have very poor venous access. A much simpler dried blood spot approach, testing for antibodies to HCV, HBV, and HIV, which requires only a very small amount of blood to be taken, has been piloted by the North West Wales Substance Misuse Service amongst individuals who do not wish to undergo venepuncture. Positive DBS test results require confirmation with venepuncture tests. Data from the North Wales pilot suggest that the dried blood spot testing protocol is both feasible and likely to increase the numbers of individuals coming forward for testing.

Aim of service development

1. To improve the current low rates of HCV and HBV diagnosis amongst injecting drug users in Wales
2. To improve HIV diagnosis amongst injecting drug users in Wales
3. To monitor the prevalence of infection amongst individuals coming forward for testing