[Prevalence of tuberculosis infection in students in the city of Tijuana, Mexico]. / Prevalencia de infección tuberculosa en escolares de la ciudad de Tijuana, México.

OBJECTIVE: To determine the prevalence of tuberculosis infection in school children from Tijuana, Mexico. MATERIAL AND METHODS: A study sample was randomly chosen from the municipal school registry and 1,131 elementary and high school children were included. All received one doses of PPD 5TU (Mantoux). Subjects with induration > or = 10 mm were considered positive reactors. RESULTS: The overall prevalence of positive reactors was 57%. The proportion of positive reactors was significantly higher among BCG-immunized subjects than in non-immunized individuals (59.7 vs 45.6%; p < 0.001). Correlation was not significant between age of immunization with BCG and diameter of induration. CONCLUSIONS: The prevalence of tuberculosis infection in Tijuana is extremely high; this fact has important implications in the control of tuberculosis in this region.