Estimating Prevalence and Number of People With Chronic Hepatitis B: A Multiplier Method Based on Public Health Surveillance Data in UK (2015-2021).

Estimates of chronic hepatitis B virus (HBV) prevalence and critically the amount of infection that is undiagnosed or unlinked to care are uncertain-even in countries like UK where vertical transmission and overall prevalence are very low. In the absence of country of birth data, we aim to estimate HBV prevalence through combining public health surveillance data on antenatally screened women by ethnic group and multipliers generated from non-antenatally screened populations by ethnic group with English population denominators. Of 714,287 women aged 16-49 years with ethnic group data tested as part of antenatal care between 2015 and 2021, 4174 (0.6%) were HBsAg-positive; 94% in people of ethnic groups other than White British. Of 1,447,467 people tested for HBsAg with ethnic group data from other testing sources (primary and secondary care excluding occupational health and renal services), 27,628 (1.9%) were HBsAg-positive; 87% in people of ethnic groups other than White British. We estimate that the overall number and prevalence of people with chronic hepatitis B in England is 268,767 (95% CI: 227,896-314,044) and 0.58% (95% CI: 0.50-0.68). Approximately two-thirds were male, one-third female, and 68% were aged under 50. We estimate that over 83% of HBV infections are in people of ethnic groups other than White British, with 23% in people from Black ethnic groups, 21% from other White ethnic groups and 19% in Asian ethnic groups. These estimates are the first step towards establishing whether England can meet World Health Organisation targets to eliminate HBV as a public health problem-using methods that can also be used by other countries.