ABSTRACT:
International border territories represent critical settings for global health equity, as they concentrate social vulnerability, population mobility and asymmetric access to health systems. In rural and remote areas, these challenges are intensified by geographic isolation, workforce instability and fragile care coordination. Evidence from Brazilian rural and remote municipalities highlights persistent barriers to access, continuity and system sustainability.¹² This study analyzes primary health care (PHC) in Oiapoque, a remote Brazilian municipality bordering French Guiana, emphasizing how border dynamics shape inequities, inclusion challenges and the sustainability of health systems. A qualitative field study was conducted in October 2025 as part of a broader national investigation on PHC in rural and remote municipalities in Brazil. Data collection included field visits to health facilities and semi-structured interviews with health managers, professionals and community health workers. Thematic analysis focused on governance, financing mechanisms, workforce dynamics, access to specialized care and cross-border influences on care trajectories, drawing on analytical approaches previously applied in studies of rural and remote PHC.¹³ PHC in Oiapoque operates under chronic structural inequities related to population underestimation in federal financing, intense cross-border mobility and limited service integration. Similar to findings reported in other remote municipalities, workforce turnover, insufficient infrastructure and weak referral and counter-referral systems undermine continuity of care.¹ Residents frequently navigate between Brazilian and French health systems, producing fragmented care pathways. Adaptive strategies such as itinerant teams and telemedicine have expanded access and inclusion, particularly for rural, riverine and socially marginalized populations, echoing experiences documented during health emergencies in remote territories.² However, these strategies remain constrained by fragile digital infrastructure and governance gaps. PHC in international border territories requires differentiated financing models and governance toward equity and inclusion. Border conditions should be recognized as structural determinants of health, demanding tailored public health responses to ensure care in remote Amazonian regions.