Background: The coronavirus disease 2019 (COVID-19) has recorded approximately 8.6 million confirmed cases and more than 450.000 deaths worldwide. As of today, Brazil remains the second most affected country, with more than 1 million confirmed cases and more than 50,000 related deaths. This study aimed to evaluate the temporal trend of the frequency of face mask use among Brazil’s general population.
Method: A cross-sectional survey method was adopted in this study. Online survey regarding sociodemographic and protective personal measures against COVID-19 was used to collect data. Data were collected from April 17 to May 15, 2020. The frequency of face mask use was divided into five categories: “never,” “rarely,” “sometimes,” “frequently,” and “always.” Joinpoint regression model was employed to analyze the daily percentage change (DPC) of each category. Ethics aspects were considered.
Results: A total of 14,756 volunteers comprised the study sample. The “frequently” and “always” categories represented 71% of the sample, with the former being superior to the latter (39.4% vs. 31.6%, respectively). Temporal trend analysis showed two trend periods for all categories. The “never,” “rarely,” and “sometimes” categories decreased in the first period and stabilized in the second period. Conversely, the “frequently” and “always” categories showed an upward trend. Like other categories, the “frequently” category had stabilized in the second period. However, the “always” category still showed an increasing trend in the second period. The association analysis results showed a decrease in the use of face masks in women, postgraduate people, those aged above 35 years, and those earning more than seven times the federal monthly income minimal wage. However, the use of masks increased among young people and those with elementary to graduate degrees. The “always” use of face masks increased in the south and decreased in the southeast of Brazil.
Conclusion: The preponderance of the “frequently” category and the slow DPC in the second trend period of the “always” category suggest the necessity of further enforcement of the use of face masks in Brazil. The adaptation of this new habit among Brazilians is time demanding, and thus strategies must be implemented in a more natural way.