Infectious disease testing of UK-bound refugees: a population-based, cross-sectional study

The UK, like a number of other countries, has a refugee resettlement programme. External factors, such as higher prevalence of infectious diseases in the country of origin and circumstances of travel, are likely to increase the infectious disease risk of refugees, but published data is scarce. The International Organization for Migration carries out and collates data on standardised pre-entry health assessments (HA), including testing for infectious diseases, on all UK refugee applicants as part of the resettlement programme. From this data, we report the yield of selected infectious diseases (tuberculosis (TB), HIV, syphilis, hepatitis B and hepatitis C) and key risk factors with the aim of informing public health policy.

We examined a large cohort of refugees (n = 18,418) who underwent a comprehensive pre-entry HA between March 2013 and August 2017. We calculated yields of infectious diseases stratified by nationality and compared these with published (mostly WHO) estimates. We assessed factors associated with case positivity in univariable and multivariable logistic regression analysis.

The number of refugees included in the analysis varied by disease (range 8506-9759). Overall yields were notably high for hepatitis B (188 cases; 2.04%, 95% CI 1.77-2.35%), while yields were below 1% for active TB (9 cases; 92 per 100,000, 48-177), HIV (31 cases; 0.4%, 0.3-0.5%), syphilis (23 cases; 0.24%, 0.15-0.36%) and hepatitis C (38 cases; 0.41%, 0.30-0.57%), and varied widely by nationality. In multivariable analysis, sub-Saharan African nationality was a risk factor for several infections (HIV: OR 51.72, 20.67-129.39; syphilis: OR 4.24, 1.21-24.82; hepatitis B: OR 4.37, 2.91-6.41). Hepatitis B (OR 2.23, 1.05-4.76) and hepatitis C (OR 5.19, 1.70-15.88) were associated with history of blood transfusion. Syphilis (OR 3.27, 1.07-9.95) was associated with history of torture, whereas HIV (OR 1521.54, 342.76-6754.23) and hepatitis B (OR 7.65, 2.33-25.18) were associated with sexually transmitted infection. Syphilis was associated with HIV (OR 10.27, 1.30-81.40).

Testing refugees in an overseas setting through a systematic HA identified patients with a range of infectious diseases. Our results reflect similar patterns found in other programmes and indicate that the yields for infectious diseases vary by region and nationality. This information may help in designing a more targeted approach to testing, which has already started in the UK programme. Further work is needed to refine how best to identify infections in refugees, taking these factors into account.