OBJECTIVE: To study the annual risk of tuberculosis infection among school age children resident in the Federal District, during 1997. METHODOLOGY: A cross-sectional study was carried out among 1,328 eight-year-old students, living in the cities of Ceilândia and Guará, in the Federal District, utilizing the Dam & Ritze model to determine prevalence rates and the method suggested by Ruffino-Netto for the annual risk. The data collected was processed using Excel and SPSS 9.0 software. Statistical analysis included Confidence Intervals and Chi-squares. The study was approved by the Ethics Research Committee, which requested that the adults responsible for the children signed a Term of Free and Full Consent. RESULTS: The proportions of those infected and non-infected by Mycobacterium tuberculosis did not differ statistically (chi2=3.8416) in the two cities. For 1997, the prevalence of tuberculosis was 3.3% and the annual risk of infection was 0.42% for the children studied. CONCLUSION: The authors expected to find a reduction in the IR in the Federal District. Based on this information, the area can be characterized as of medium intensity for tuberculosis infection but with a tendency towards the improvement in the epidemic.
Tuberculosis; Tuberculosis incidence; Annual risk of infection