Tuberculosis incidence among infected contacts detected through contact tracing of smear-positive patients

Background The contacts of people with pulmonary tuberculosis (PTB) have a high risk of becoming infected and developing tuberculosis (TB). Our aim was to determine the incidence of TB and its risk factors in a cohort of contacts with latent TB infection (LTBI) detected through contact tracing of sm...

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Detalles Bibliográficos
Autores: Martín Sánchez, Mario|||0000-0002-2221-5331, Brugueras Torrella, Silvia|||0000-0001-6439-0050, De Andrés, Anna|||0000-0001-6980-2050, Simón Vivan, Pere|||0000-0002-5057-7583, Gorrindo, Pilar, Ros, Miriam|||0000-0002-3659-8222, Masdeu, Eva, Millet, Joan Pau|||0000-0003-0200-2459, Caylà, Joan A.|||0000-0003-3891-111X, Orcau, Àngels|||0000-0001-8109-7614
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:223455
Acceso en línea:https://ddd.uab.cat/record/223455
https://dx.doi.org/urn:doi:10.1371/journal.pone.0215322
Access Level:acceso abierto
Palabra clave:Adolescent
Adult
Child
Child, Preschool
Female
Follow-Up Studies
Humans
Incidence
Latent Tuberculosis
Male
Middle Aged
Retrospective Studies
Tuberculosis, Pulmonary
Descripción
Sumario:Background The contacts of people with pulmonary tuberculosis (PTB) have a high risk of becoming infected and developing tuberculosis (TB). Our aim was to determine the incidence of TB and its risk factors in a cohort of contacts with latent TB infection (LTBI) detected through contact tracing of smear-positive PTB cases. Methods and findings We performed a population-based retrospective cohort study including contacts that had LTBI, and were contacts of people with PTB who started treatment between 2008 and 2014. We followed up contacts until they developed TB or until the end date for follow-up (31st December 2016). We used Kaplan-Meier curves to compute incidence at 2 and 5 years, and Cox regression to compute hazard ratios (HR) and their 95% confidence intervals (CI). We analyzed 3097 close contacts of 565 PTB cases. After exclusion of 81 co-prevalent TB cases, 953 contacts had LTBI, of which 14 developed TB. Their risk of developing TB after two and five years was 0.7% (CI: 0.3-1.6) and 1.8% (CI: 1.1-3.1) respectively. Contacts who had not been referred for LTBI treatment had a 1.0% (CI: 0.2-4.0) risk at 5 years. Risk of developing TB at 5 years was 1.2% (CI: 0.5-3.0) among people who completed treatment, and 11.1% (CI: 5.1-23.3) for those who did not. Risk factors for TB were not completing LTBI treatment (HR 9.4, CI: 2.9-30.8) and being female (HR 3.5, CI: 1.1-11-3). Conclusions LTBI treatment plays a fundamental role in decreasing the risk of developing TB. It is necessary to achieve a maximum contact tracing coverage and the highest possible compliance with LTBI treatment.