Introduction: A considerable increase in asthma and atopy prevalence has been noticed worldwide through the last decades, however, in our country, epidemiological data are still insufficient. Objective: This study was carried out to determine the prevalence of asthma and atopy in a group of students, and compare these data with those found in two previous studies undertaken in Porto Alegre, Rio Grande do Sul. Methods: Asthma prevalence was identified through a questionnaire applied to 855 students from five schools of Porto Alegre. The students submitted to skin tests who presented, at least, one positive reaction were considered atopic. The signature of an informed consent from one of the parents was required for the skin test performance. Results: Prevalence was found to be 42.5% and 22% of cumulative and active asthma, respectively, with predominance in females. Atopy was identified in 50.1% of the sample. These results were significantly higher than the 6.7% (1980) and 16% (1989) of cumulative asthma, 10.9% (1989) of active asthma and 15.8% (1980) of atopy found in the two previous studies. Conclusion: A high prevalence of asthma and atopy was identified in our students. Future studies should be performed to elucidate the phenomenon herein demonstrated.

Keywords: Asthma. Epidemiology. Atopy.