Preventive behaviors for COVID-19 in Chile: Lessons from a population follow-up for 2021 and 2022.

Introduction: The rapid emergence of COVID-19 urged policy responses worldwide, focusing on vaccination and mobility restrictions. Chile represents a unique scenario for analyzing personal preventive measures amid intensive communication and vaccination campaigns. This study aims to explore changes in population adherence to non-pharmacological preventive measures during the pandemic and the factors that explain this adherence each year.

Methods: 386 individuals who participated in two population-based studies (2021 and 2022) were considered. An interview was conducted to measure adherence to self-care practices, and case and contact tracing by the health authorities. The Wilcoxon signed-rank test was performed to measure change between 2021 and 2022, bivariate analysis, and a linear regression model for each year were performed.

Results: Mask-wearing in public places was the most commonly used measure (95.9% in 2021, 89.9% in 2022). Follow-up of cases and cases contacts by the health authority had high coverage in 2021 (94.3% and 83% respectively). A greater decrease was observed in contact tracing in 2022 totaling 33.3%. An increase in the score of adherence to preventive practices was observed in 2022 (p < 0.00). The regression model showed in 2021 that women were more likely to adopt preventive behaviors (95% confidence interval: 0.27 to 1.13) and the overweight/obese had higher adherence compared to normal body mass index (95% confidence interval: 0.06 to 0.98). In 2022 being a young adult (30 to 49 years) predicted the adoption of behavioral precautions (95% confidence interval: 0.00 to 1.32).

Conclusions: Adherence to preventive measures increased even with high vaccination coverage, likely due to the epidemiological situation with the Omicron variant circulating in 2022.