Cost-effectiveness of tuberculosis infection screening and treatment among high-tuberculosis risk immigrants and asylum seekers in The Netherlands: A cohort modelling study.

BACKGROUND

We evaluated the cost-effectiveness of TB infection (TBI) screening and TB preventive treatment (TPT) for immigrants, asylum seekers, and settled migrants in The Netherlands.

METHODS

We used a deterministic cohort model that captures the natural history of TBI and TB disease for a migrant cohort in the country of origin (pre-entry) and in The Netherlands (post-entry). We fitted the pre-entry force of infection to Interferon Gamma Release Assay (IGRA) positivity rates from an implementation pilot study, and chest X-ray (CXR) positivity from the national entry-screening programme. We compared the costs per quality adjusted life year (QALY) gained for TBI screening with CXR screening over a 20-year time-horizon, accounting for parameter uncertainty by producing predictions for over 1000 unique parameter combinations that fit the data.

RESULTS

TBI screening uniformly resulted in an increase in QALYs gained compared to current CXR-based screening policies. For immigrants, <10 % of parameter combinations predicted TBI entry screening to be more cost-effective than CXR screening under observed TPT completion rates (36 %). However, this changed to nearly 100 % of parameter combinations for immigrants coming from countries with a TB incidence of ≥100 per 100,000 when applying TPT completion rates as observed in asylum seekers (72 %). For asylum seekers, 100 % of parameter combinations predicted cost-effectiveness, while 0 % predicted TBI screening to be cost-effective among settled migrants.

CONCLUSIONS

TBI entry screening is a cost-effective alternative to CXR entry screening for immigrants and asylum seekers coming from high TB endemic countries, provided TPT completion is sufficiently high.