Context: Variations between different nations’ responses to the COVID-19 pandemic highlight the challenges of a unified global pandemic response. Cross-national comparison of different nations’ knowledge, perceptions, and mitigation behaviors related to COVID-19 may help identify cultural differences that must be addressed in order to facilitate a unified response. In particular, by identifying culturally-driven differences in health messaging, we may better be able to generate culturally-specific health messaging to improve understanding and mitigation behavior. Objective: Compare the factors that influence public knowledge, trust, and intent to comply with public health recommendations in Brazil and the US. Study Design: Mixed-methods cross sectional survey distributed in English and Portuguese and distributed through snowball recruiting. Setting: Online survey early in the COVID-19 pandemic. Population Studied: 73 adults from Brazil and a 1:1 US cohort matched by gender, age, date of survey completion, education status and social status. Outcome Measures: Quantitative comparisons of COVID-19 knowledge scores, intent to comply with CDC and WHO recommendations, preferred information sources, and level of trust in information sources will be made using Chi-squared tests to 95% confidence. Conventional content analysis will be used to analyze responses to five open-ended, free-text questions using NVivo 12. Four coders (two for each country) will independently generate a qualitative codebook and code all responses to an inter-rater reliability of ≥ 0.65. Qualitative differences in thematic outcomes will then be compared and contrasted. Results: The matched cohort is similar across all five requirements (chi-square match p>.05). Quantitative and qualitative data analyses are in progress. Outcomes to be Reported: Quantitative comparisons as described. Qualitative themes will be merged and aligned with conclusions drawn from the quantitative data, and presented in a joint display for each quantitative construct. We hypothesize there will be differences in responses due to cultural distinctions, economic disparities, structural differences in health systems, and government actions against the pandemic. These will provide insight into factors that influence compliance with public health recommendations, which should enable better, culturally-specific, health messaging.