Characterization of Potential Risk Pathways for African Swine Fever Introduction Into Brazil

African swine fever (ASF) poses a serious threat to global swine production, and its reintroduction into Brazil, the world's third-largest pork exporter, would have severe socioeconomic consequences. This study characterized the potential risk pathways for ASF introduction in Brazil by analyzing three key aspects: seizure of informally imported animal-origin products (AOP) at airports, entry of individuals from ASF-affected countries into Brazil, and the profile of immigrant workers. A total of 4301.38 kg of AOP from ASF-affected countries, mainly China, Italy, Nigeria, and Germany, were seized at Brazilian airports in 2023. The most common nationalities involved were Chinese and Brazilian. Patterns of traveler entry from ASF-affected countries revealed relationships among border entry points, visa types, and continent of origin. Seasonal patterns of international passenger arrivals were significantly correlated with the average seasonal index (ASI) of ASF outbreaks in Europe (Spearman r = 0.69, p < 0.05) and Asia (r = 0.62, p < 0.05), with both increasing during periods of intensified human mobility, such as holiday seasons, suggesting that human movement may represent one of several factors contributing to this seasonal alignment. Furthermore, the occupational and spatial profiles of immigrant workers from these countries showed that many were employed in roles involving direct contact with livestock and lived in states with high pig densities. These findings provide crucial evidence for implementing risk-based surveillance. Additionally, the results underscore the importance of targeted educational measures for immigrant workers involved in livestock activities, aiming to mitigate the risk of ASF introduction and spread in Brazil.