Drivers determining tuberculosis disease screening yield in four European screening programmes: a comparative...

Area of Science:

• Public Health
• Epidemiology
• Infectious Disease Control

Background:

• The World Health Organization's End TB Strategy prioritizes early tuberculosis (TB) diagnosis through screening in high-risk groups, notably migrants.
• Understanding variations in TB detection rates among migrant populations is crucial for effective TB control strategies.

Purpose of the Study:

• To analyze the primary factors influencing differences in TB detection yield across four major migrant TB screening programs.
• To provide evidence for refining TB control planning and assessing the feasibility of a unified European approach to migrant TB screening.

Main Methods:

• Individual TB screening data from Italy, the Netherlands, Sweden, and the UK were aggregated.
• Multivariable logistic regression models were employed to identify predictors and interactions affecting TB case yield.

Main Results:

• Over 2.3 million screening episodes identified 1658 TB cases (yield: 72.0 per 100,000).
• Significant predictors of higher TB yield included older age (≥55 years), asylum seeker or settlement visa status, close TB contact, and higher TB incidence in the country of origin.
• Interactions were observed between migrant type, age, and country of origin, with asylum seekers showing a consistently elevated risk above a 100 per 100,000 incidence threshold.

Conclusions:

• Close contact, increasing age, country of origin incidence, and specific migrant groups (asylum seekers, refugees) are key determinants of TB yield.
• While TB yield generally correlates with country of origin incidence for most migrants, asylum seekers exhibit a high, independent risk potentially linked to transmission and reactivation during migration.
• Findings have implications for targeted TB screening strategies, particularly for vulnerable migrant populations.