Hepatitis B contact tracing: what works?

In 2012, over 239000 people were living in Australia with chronic hepatitis B (CHB). Australia's Second National Hepatitis B Strategy (2014) recommends testing contacts to increase identification of people with CHB, but it is generally poorly performed. CHB prevalence in Australia is increasing and contact tracing (CT) remains an untapped strategy for identifying infected individuals. A systematic CT system has been established in a government-funded primary health centre in Melbourne, which services 2000 refugees. This mixed-methods study aimed to describe the structure of the CT system, determine its effectiveness and identify enablers of success. The CT system's structure was elicited from field notes. CT effectiveness (proportion of contacts traced and serologically confirmed as infected or immune to HBV) was determined by auditing clinical records. Semi-structured interviews with seven health professionals were thematically analysed to identify enablers of CT success. Overall, 122 CHB index cases had 420 contacts. And 90.0% (n=380) of 420 contacts were successfully traced, 68.0% (n=83) of index cases had 100% of their contacts successfully traced and 80.7% (n=339) of all contacts were immune; 28.8% (n=121) had evidence of previous exposure and 55.0% (n=231) had evidence of vaccination. Also, 8.1% (n=34) were chronically infected. Interviews elicited seven themes important to the success of the CT system: Teamwork; Organisation; Health professional expertise; Patient education; Centralisation of the system; Influence of patient culture; and Use of nurses in CT. Teamwork and Organisation were previously unidentified in the literature. This CT system is successful and could be implemented elsewhere, provided an organised, cohesive, nurse-led team is established.