High yield from repeated testing for tuberculosis among high-risk citizens in Denmark

Area of Science:

• Public Health
• Infectious Disease Epidemiology
• Social Medicine

Background:

• Tuberculosis (TB) screening is implemented in urban areas of low-incidence countries like Denmark.
• Focus on socially marginalized populations is crucial for TB control.
• This study examines TB and latent TB infection (LTBI) screening in western Denmark (2014-2019).

Purpose of the Study:

• To describe findings from TB and LTBI screening programs.
• To evaluate screening effectiveness in a specific demographic.
• To inform public health strategies for TB prevention in vulnerable groups.

Main Methods:

• Retrospective data collection from 1024 socially marginalized citizens.
• Utilized interferon-gamma release assays (IGRA), spot sputum tests, and chest X-rays.
• Screening conducted in urban areas of western Denmark between 2014 and 2019.

Main Results:

• Overall TB incidence was 2148/100,000; number needed to screen was 39.
• LTBI incidence using IGRA was 17,500/100,000.
• TB incidence was similar for spot sputum tests (2.5) and IGRA (2.7); 38.9% of TB cases found after repeat screening rounds.

Conclusions:

• High incidence of TB and LTBI observed in socially marginalized populations in Denmark.
• Spot sputum testing and IGRA are comparable for TB diagnosis in this setting.
• Highlights the need for targeted screening programs for vulnerable groups.