[01] Dalila Martínez-Hall, Pedro Kourí Institute of Tropical Medicine, Havana City, Cuba. [02] Susana Borroto-Gutiérrez, Pedro Kourí Institute of Tropical Medicine, Havana City, Cuba. [03] Lellanis Arroyo-Rojas, Pedro Kourí Institute of Tropical Medicine, Havana City, Cuba. [04] Edilberto González-Ochoa, Pedro Kourí Institute of Tropical Medicine, Havana City, Cuba.

Background: Tuberculosis transmission is a risk to health care workers (HCW) Objectives: To determine the prevalence of latent tuberculosis infection (LTBI), the annual risk of infection and its possible association with some predictive variables. Methods: A cross-sectional study in 1063 HCW at La Lisa municipality policlinics, Havana, was carried out during 2009-2011; a Tuberculin Skin Test (TST) was applied, along with a structured questionnaire exploring general and on exposition data. The reading was performed in 905 HCW at 72 hours, defining as positive ≥10mm induration and tuberculin conversion as ≥10 mm increasing in the second TST of those previously negative. To prove the possible influence of predictive variables on the presence of infection, a bivariate analysis and a multivariate model were applied. Results: The prevalence of LTBI was 15,2%, with 3,7% of AIR. The highest prevalence in Berovides Policlinic (19,3%) and the lowest in Fernández (10,5%). The highest annual risk of infection was in Labra (6,4%) and the lowest in Fonseca (1%). The variables possibly associated to LTBI were: belonging to Labra and Berovides policlinics, having contact with tuberculosis patients, being ≥20 years working there and belonging to the following occupational groups: administrative, nurse, maintenance staff and health technicians. Conclusions: The transmission of tuberculosis infection, even in low levels, is possibly associated to the labor environment; so it would be advisable to value the application of preventive chemotherapy in these personnel and to maintain the appropriate measures of infection control in the institutions.

Tuberculosis, Latent Tuberculosis Infection, Prevalence, Primary Health Care

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