[Tuberculin reactivity among ninth-grade schoolchildren in the city of Havana, Cuba].

Objective: To determine the proportion of 14-year-old schoolchildren in the city of Havana, Cuba, with a positive tuberculin skin test, as an indicator of the prevalence of tuberculosis infection among them.

Methods: Using single-stage cluster sampling, 1 936 Mantoux (tuberculin) tests were carried out with ninth-grade students (cohort born in 1985) during the 1999- 2000 school year in 20 basic high schools randomly selected in Havana. The tests were performed according to the standard technique recommended by the World Health Organization, and they were read after 72 hours.