Estimating the epidemiology of chronic Hepatitis B Virus (HBV) infection in the UK: what do we know and what are we missing?

Abstract

Background: HBV is the leading global cause of cirrhosis and primary liver cancer. However, the UK HBV population has not been well characterised, and estimates of UK HBV prevalence and/or incidence vary widely between sources. We summarised datasets that are available to represent UK CHB epidemiology, considering differences between sources, and discussing deficiencies in current estimates. Methods: We searched for estimates of CHB case numbers in the UK (incorporating incidence and/or prevalence-like data) across a range of available sources, including UK-wide reports from government bodies, publications from independent bodies (including medical charities and non-governmental organisations) and articles in peer-reviewed scientific journals to collate estimated positivity rates. An alternative proxy for population prevalence was obtained via the UK antenatal screening programme which achieves over 95% coverage of pregnant women. Results: We identified six CHB case number estimates, of which three reported information concerning population subgroups, including number of infected individuals across age, sex and ethnicity categories. Estimates among sources reporting prevalence varied from 0.27% to 0.73%, congruent with an estimated antenatal CHB prevalence of <0.5%. Discussion: Estimates varied by sources of error, bias and missingness, data linkage, and substantial “blind spots” in consistent testing and registration of HBV diagnoses. The HBV burden in the UK is likely to be concentrated in vulnerable populations who may not be well represented in existing datasets including those experiencing socioeconomic deprivation, ethnic minorities, people experiencing homelessness and people born in high-prevalence countries. Together, these factors could lead to either under- or over-estimation of overall prevalence, and additional efforts are required to provide estimates that best reflect the whole population. Multi-parameter evidence synthesis and back-calculation model methods similar to those used to generate estimates of HCV ad HIV population-wide prevalence may be applicable to HBV.

Hepatitis B virus (HBV) screening, linkage and retention-in-care in inclusion health populations: Evaluation of an outreach screening programme in London

“…UKHSA estimates the overall population prevalence is 0.45% (95% CI 0.35% to 0.60%). This is lower when estimated using primary care data (0.05%), suggesting that many people living with HBV may not be registered with their GP and highlights a gap in diagnosis ( 10 , 20 ). Our data point towards an increased prevalence of HBV in IH populations compared to the general population, supporting the hypothesis that some of those undiagnosed may be in IH populations.…”

Analysis of electronic health record data of hepatitis B virus (HBV) patients in primary care: hepatocellular carcinoma (HCC) risk associated with socioeconomic deprivation and reduced by statins

“…CHB prevalence has not been robustly estimated in many settings, including the UK (6), and groups at the highest risk of morbidity and mortality have not been well characterised. Furthermore, even in well-defined CHB populations, treatment coverage and eligibility are often unreported.…”

“…Furthermore, even in well-defined CHB populations, treatment coverage and eligibility are often unreported. Regional HBV reports from UK public health services (UK Health Security Agency, previously Public Health England) have included neither overall estimates of the proportion of CHB individuals receiving antiviral treatment, nor estimates stratified by relevant subgroups such as age, sex and ethnicity (6–10).…”