In areas of high endemicity, the lifetime infection rate is above 50%, and more than 8% of the population are chronic carriers.5 Infection in such regions is typically acquired in childhood, either horizontally from other children or perinatally from maternal carriers. By contrast, parenteral transmission is common in Australia, and fewer than 2% of the population are chronic HBV carriers. Hepatocellular carcinoma is the sixth most common cancer worldwide, and half of all cases are caused by HBV.6 HBV is the second most important RGFP966 carcinogen after cigarette smoke. In dialysis units both patient-to-patient and patient-to-staff transmission of the virus have been recognized

since the 1960s. Before the advent of vaccination, FK506 some success in limiting the spread of HBV was achieved by dialysing seropositive patients separately from those who were seronegative. This followed the publication in the UK of the Rosenheim Report in 1972,7 which set out a code of practice for reducing transmission of hepatitis among dialysis patients. In 1977, guidelines were published in the USA to reduce HBV infection in dialysis units.8 The incidence of new hepatitis B infections in US dialysis patients subsequently fell from 6.2% in 1974 to 1% by 1980.9 Testing of a vaccine began in the 1970s,

and this came into widespread clinical use from the early 1980s.10,11 This further reduced the risk of HBV infection in the dialysis setting. Nevertheless, although rates of new infection are now low,12 hepatitis B continues to exist in dialysis populations. Prevalence

rates tend to be dependent on baseline population rates. An analysis of data from the Dialysis Outcomes and Practice Patterns Study showed an HBV prevalence of 0–6.6% across dialysis facilities in Western Europe, Japan and the USA.13 In contrast, a registry study of Asia–Pacific countries found the prevalence of hepatitis B surface antigen (HBsAg) positivity ranged between 1.3% and 14.6%.14 Reports from much smaller cohorts elsewhere have indicated HBsAg positivity rates of 13.3% in Turkey, and 2.4–10% next in Brazil.15–17 In addition to being at increased risk of infection, it has been demonstrated that HD patients are more likely to become chronic carriers of HBV than members of the general population.18 Patients with chronic kidney disease (CKD) have impaired host defences against viral infections.19 Consequently, risk of acquisition is increased in dialysis populations regardless of dialysis modality. Before the introduction of erythropoietin therapy, CKD patients were also at increased risk of infection via transfusion of contaminated blood products. The HD procedure presents the opportunity for blood contact with contaminated equipment, injection of liquids harbouring virus, and exposure of broken skin or mucous membranes to infection. HBV is particularly persistent in the environment, and may survive for more than a week on surrounding surfaces.