Abstract: Hepatitis C is the most commonly diagnosed notifiable communicable infection in Australia. The Hepatitis C Virus Projections Working Group of the Australian National Council on AIDS, Hepatitis C and Related Diseases (ANCAHRD) released the report Estimates and Projections of the Hepatitis C Epidemic in Australia 2002 which stated that in 2001 approximately 210 000 people in Australia had hepatitis C antibodies and approximately 16 000 new infections were occurring annually. Although the virus may be cleared after infection, it persists in 65–85 per cent of those infected. Of these cases, 5–10 per cent develop cirrhosis after 20 years and 3–5 per cent develop hepatocellular carcinoma. Thus, hepatitis C represents a significant public health concern. A diagnosis of hepatitis C also has multiple implications in relation to an individual’s work, family and quality of life. Caring for a person diagnosed with hepatitis C calls for informed and sensitive management. Health professionals, infected people and the community recognise that clear and rigorous guidelines for diagnosing and monitoring hepatitis C infection are needed and that the guidelines should take account of the life of the infected individual as well as of the populations at risk and their needs. The National Hepatitis C Testing Policy has been formulated under the auspices of the Australian National Council on AIDS, Hepatitis C and Related Diseases (the Commonwealth’s principal independent advisory body on hepatitis C) and the Intergovernmental Committee on AIDS, Hepatitis C and Related Diseases (the intergovernmental committee responsible for implementation of the National Hepatitis C Strategy). The policy is intended to provide advice to government, health professionals, industry, hepatitis C–infected individuals, and the community in general, about matters associated with testing. Anti-HCV antibody testing first became available in 1990. The number of hepatitis C antibody tests carried out each year in Australia is approaching 2 million (including blood service and diagnostic testing) and about 50 000 for supplemental immunoassay tests. New technologies have offered further dimensions in testing strategies. Qualitative and quantitative nucleic acid tests (NAT) are useful in detecting infection in the early stages and in assessing clearance of the virus and the effect of treatment. Qualitative NAT can be used to determine if infants of infected mothers have been infected. Genotype testing is useful in predicting the response to treatment because some hepatitis C subtypes are more sensitive to therapy than others. In addition to these tests, short incubation immuno-assays are available and home kits are being developed for marketing. The National Hepatitis C Testing Policy offers clarification on the use of hepatitis C tests and the interpretation of diagnostic tests in the context of other laboratory tests and specific clinical situations. There are 32 recommendations. Recommendations 1 to 19 outline the principles for hepatitis C testing and emphasise the need for individuals to be informed about testing and to be tested voluntarily. Testing must be of benefit to the individual, and confidentiality must be maintained at all levels of testing. People with hepatitis C should have access to treatment and ongoing monitoring. Particular attention should be paid to groups such as Aboriginal and Torres Strait Islander peoples and people from culturally and linguistically diverse backgrounds, who may have difficulty gaining access to health services; populations at risk, such as injecting drug users and people in custodial settings, also warrant particular attention. Recommendations 20 to 29 outline diagnostic strategies. Appropriate testing standards are to be applied by all laboratories undertaking testing for hepatitis C. Minimum practices, which should be adopted by all laboratories, include the need to confirm antibody reactivity by two separate immuno-assays based on different antigens and different immuno-assay formats. Discordant test results in two immunoassays may require additional testing by qualitative NAT or referral to a reference laboratory, or both. The National Serology Reference Laboratory should keep laboratories up to date on appropriate combinations of immuno-assays, to avoid common cross-reactivity between tests. The utility of qualitative NAT in testing newly diagnosed hepatitis C sero-positive individuals and in testing infants born to hepatitis C sero-positive mothers is discussed in Chapter 6. The use of short incubation tests is not supported—except in the case of screening potential organ donors, when the tests should be performed by suitably trained laboratory personnel. Home sampling or testing is not supported for the Australian situation. The regulation of hepatitis C test kits and the supporting Quality Assurance Program are dealt with in Recommendations 30 to 32. An outline for a classification system for hepatitis C tests and test kits is presented; the system offers a choice of test protocols within a given situation and a framework for evaluation of test kits and for incorporating new technology as it emerges. The policy recommends that it be a condition of registration of hepatitis C kits by the Therapeutic Goods Administration that laboratories using the kits participate in the National Serology Reference Laboratory’s hepatitis C Quality Assurance Program. Standard and reference testing for hepatitis C should be provided by public and private sector laboratories that comply with the National Association of Testing Authorities – Royal College of Pathologists of Australasia audit and accreditation mechanisms, according to National Pathology Accreditation Advisory Committee guidelines. The National Hepatitis C Testing Policy will clarify for all concerned the testing parameters for hepatitis C and guide the approach to diagnosis and management.