Immigrant screening for latent tuberculosis in Norway: a cost-effectiveness analysis

Area of Science:

• Public Health
• Epidemiology
• Health Economics

Background:

• Tuberculosis (TB) incidence has risen in Norway since the mid-1990s.
• Immigrants are screened for latent TB infection (LTBI) to prevent TB disease reactivation.
• Previous cost-effectiveness analyses for LTBI screening in Norway are lacking.

Purpose of the Study:

• To estimate the costs of LTBI and TB disease screening and treatment in Norway.
• To model the cost-effectiveness of different LTBI screening algorithms.
• To determine the expected value of perfect information (EVPI) for LTBI screening.

Main Methods:

• Development of a cost-effectiveness model for four LTBI screening algorithms.
• Utilizing avoided TB disease cases as the primary health outcome.
• Calculation of EVPI to identify areas for improved screening cost-effectiveness.

Main Results:

• Treatment costs: €1938 for LTBI, €15,489 for TB disease per case.
• Three cost-effective algorithms identified, varying by cost-effectiveness threshold.
• Screening all immigrants with interferon-gamma release assays (IGRA) requires the highest threshold (€28,400).

Conclusions:

• TB disease screening and treatment represent the largest cost component.
• LTBI screening and treatment costs are comparatively minor.
• Increasing treatment of IGRA-positive immigrants significantly reduces costs per avoided TB case.