Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Feb 10;14(2):175.
doi: 10.3390/pathogens14020175.

Exposure Time to a Tuberculosis Index Case as a Marker of Infection in Immigrant Populations

Sofia Godoy  1   2 , Miquel Alsedà  1   3 , Ignasi Parrón  3 , Joan-Pau Millet  4   5   6 , Joan A Caylà  5 , Núria Follia  3 , Monica Carol  3 , Angels Orcau  6 , Diana Toledo  4   7 , Gloria Ferrús  3 , Pere Plans  3   4 , Irene Barrabeig  3 , Laura Clotet  3 , Angela Domínguez  4   7 , Jaume March-Llanes  8 , Pere Godoy  1   4   9 , On Behalf Of The Transmission Of Tuberculosis In Catalonia Spain Working Group
Affiliations

Exposure Time to a Tuberculosis Index Case as a Marker of Infection in Immigrant Populations

Sofia Godoy et al. Pathogens. .

Abstract

Background: Exposure time to a tuberculosis (TB) index case may be a marker of a recent latent tuberculosis infection (LTBI) risk. The aim of this study was to determine the LTBI risk involved in immigrant contact based on exposure time to pulmonary TB index cases. Methods: We conducted a 30-month LTBI prevalence study of pulmonary TB immigrant contacts in Catalonia (1 January 2019-30 June 2021). Contacts with LTBI were identified by means of the tuberculin skin test and/or interferon gamma release assay. Variables associated with LTBI in contacts were analysed using adjusted OR (aOR) and 95% confidence interval (CI) values. Results: LTBI prevalence was 37.4% (939/2509). Prevalence was higher in men than women (40.6% versus 33.5%; p < 0.001), and in all age groups, relative to children <5 years (12.2%; p < 0.001)). Prevalence increased with exposure time to the index case; relative to <6 h/week exposure, LTBI risk was greater for both ≥6 h/day (aOR = 2.0; 95% CI: 1.5-2.6) and <6 h/day but ≥6 h/week (aOR = 1.6; 95% CI: 1.1-2.2). Conclusions: The LTBI risk in immigrant contacts increases with recent exposure time to the index case, and may suggest recent LTBI in immigrants.

Keywords: contact tracing; epidemiology; exposure time; immigrant; latent tuberculosis infection; transmission; tuberculosis.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

References

    1. Centis R., D’Ambrosio L., Kurhasani X., Solovic I., Migliori G.B. Tuberculosis Elimination: Myth or achievable target? Arch. Bronconeumol. 2023;59:714–716. doi: 10.1016/j.arbres.2023.09.002. - DOI - PubMed
    1. World Health Organization . Framework Towards Tuberculosis Elimination in Low-Incidence Countries. World Health Organization; Geneva, Switzerland: 2014. - PubMed
    1. WHO Europe . In: Tuberculosis Elimination in the WHO European Region: Review of Key Actions, with a Special Focus on Tuberculosis Infection Management. WHO Regional Office for Europe, editor. WHO Regional Office for Europe; Copenhagen, Denmark: 2020.
    1. World Health Organization . Global Tuberculosis Report 2023. World Health Organization; Geneva, Switzerland: 2023.
    1. European Center for Disease Prevention and Control . In: Programmatic Management of Latent Tuberculosis Infection. ECDC, editor. European Center for Disease Prevention and Control; Stockholm, Sweden: 2018. pp. 1–84.

MeSH terms

LinkOut - more resources