[Molecular epidemiology of tuberculosis in Almeria (Spain). Factors associated with recent transmission]. / Epidemiología molecular de la tuberculosis en Almería. Factores asociados a transmisión reciente.

BACKGROUND: Molecular epidemiology is used in tuberculosis (TB) to identify clusters in which the cases are assumed to belong to the same recent transmission chain. An endogenous reactivation of latent TB is considered when the Mycobacterium tuberculosis isolates have a unique genotype. OBJECTIVE: To describe factors associated with recent transmission of TB in Almeria, from 2003-2007. METHODS: We conducted an observational prospective study that included patients with Mycobacterium tuberculosis positive culture. The strains were genotyped by Restriction Fragment Length Polymorphism and spoligotyping. Adjusted odds ratio and 95% confidence intervals were calculated to study factors associated with cluster groups, using a multivariate logistic regression model. RESULTS: We analysed 427 isolates, of which 71% were from males and 56.2% of them belonged to foreign residents. Furthermore, 44% were classified as a cluster. The resistance to isoniazid was 8.4%. The factors associated with clusters were age, principally the group under 10 years (adjusted OR=12.75; 95% CI, 2.52-64.58) and the group aged between 50-59 years (adjusted OR=13.85; 95% CI, 3.04-63.17), and born in Spain (adjusted OR=2.17; 95% CI, 1.41-3.36). CONCLUSIONS: In Almeria, native population, children under 10 years old and patients aged between 50-59 years have more probability to belong to the same recent transmission chain. The molecular epidemiology can be used to find out which population groups need more control and this information must be used in tuberculosis prevention programs.

Epidemiología molecular de la tuberculosis en Almería. Factores asociados a transmisión reciente / Molecular epidemiology of tuberculosis in Almeria (Spain). Factors associated with recent transmission

Introducción La epidemiología molecular aplicada a la tuberculosis (TB) permite identificar clusters, cuyos miembros se asume que pertenecen a la misma cadena de transmisión reciente. Se considera reactivación endógena cuando el aislado presenta un genotipo único. Objetivo describir los factores asociados a la transmisión reciente de la TB en Almería, en el período 2003-2007. Métodos Se realizó un estudio observacional prospectivo de pacientes con tuberculosis, cuyos aislados fueron caracterizados genotípicamente mediante Restriction Fragment Length Polymorphism y spoligotyping. Se calcularon odds ratio y sus intervalos de confianza del 95% y mediante regresión logística se analizaron los factores asociados a pertenecer a un cluster. Resultados Se analizaron 427 aislados, de los cuales el 71% procedía de varones y 56,2% de ellos pertenecían a extranjeros. Un 44% de los pacientes participaba en algún cluster. La resistencia a isoniazida fue del 8,4%. Los factores relacionados con cluster fueron la edad, fundamentalmente los menores de 10 años (OR ajustada=12,75; IC del 95%, 2,52-64,58) y el grupo entre 50 y 59 años (OR ajustada=13,85; IC del 95%, 3,04-63,17), así como los nacidos en España (OR ajustada=2,17; IC del 95%, 1,41-3,36).Conclusiones En Almería, los autóctonos presentan más posibilidades de estar implicados en una cadena de transmisión reciente, así como los pacientes de ciertos tramos de edad como los niños menores de 10 años, y los de 50-59 años. La epidemiología molecular permite conocer qué grupos de población requieren mayor control, y reorientar hacia ellos los programas de prevención de la tuberculosis (AU)

Background: Molecular epidemiology is used in tuberculosis (TB) to identify clusters in which the cases are assumed to belong to the same recent transmission chain. An endogenous reactivation of latent TB is considered when the Mycobacterium tuberculosis isolates have a unique genotype. Objective: To describe factors associated with recent transmission of TB in Almeria, from 2003-2007.Methods: We conducted an observational prospective study that included patients with Mycobacterium tuberculosis positive culture. The strains were genotyped by Restriction Fragment Length Polymorphismand spoligotyping. Adjusted odds ratio and 95% confidence intervals were calculated to study factors associated with cluster groups, using a multivariate logistic regression model. Results: We analysed 427 isolates, of which 71% were from males and 56.2% of them belonged to foreign residents. Furthermore, 44% were classified as a cluster. The resistance to isoniazid was 8.4%. The factors associated with clusters were age, principally the group under 10 years (adjusted OR= 12.75; 95% CI, 2.52-64.58) and the group aged between 50-59 years (adjusted OR= 13.85; 95% CI, 3.04-63.17), and born in Spain (adjusted OR= 2.17; 95% CI, 1.41-3.36).Conclusions: In Almeria, native population, children under 10 years old and patients aged between 50-59years have more probability to belong to the same recent transmission chain. The molecular epidemiology can be used to find out which population groups need more control and this information must be used intuberculosis prevention programs (AU)