Hepatitis B infection and immunity in migrant children and pregnant persons in Europe: a systematic review and meta-analysis.

Background: The WHO's global hepatitis strategy aims to achieve viral hepatitis elimination by 2030. Migrant children and pregnant persons represent an important target group for prevention strategies. However, evidence on the burden of chronic hepatitis B (CHB) infection and the factors affecting its incidence is lacking.

Methods: EMBASE, Global Health, Global Index Medicus, Web of Science and Medline were searched for articles in any language from 1 January 2012 to 8 June 2022. Studies reporting CHB prevalence, disease severity, complications and/or prevention strategies, including vaccination, prevention of vertical transmission and access to care/treatment for migrant children and pregnant migrants, were included. Pooled estimates of CHB prevalence and hepatitis B vaccination (HBV) coverage among migrant children were calculated using random effects meta-analysis.

Findings: 42 studies were included, 27 relating to migrant children and 15 to pregnant migrants across 12 European countries, involving data from 64 773 migrants. Migrants had a higher incidence of CHB than host populations. Among children, the pooled prevalence of CHB was higher for unaccompanied minors (UAM) (5%, [95% CI: 3-7%]) compared to other child migrants, including internationally adopted children (IAC) and refugees (1%, [95% CI: 1-2%]). Region of origin was identified as a risk factor for CHB, with children from Africa and pregnant migrants from Africa, Eastern Europe and China at the highest risk. Pooled estimates of HBV vaccine coverage were lower among UAM (12%, [95% CI: 3-21%]) compared to other child migrants (50%, [95% CI: 37-63%]).

Conclusion: A range of modifiable determinants of HBV prevalence in migrant children and pregnant persons were identified, including sub-optimal screening, prevention and continuum of care. There is a need to develop evidence-based approaches in hepatitis care for these groups, thereby contributing towards global viral hepatitis elimination goals.