Chikungunya virus: from global emergence to immunopathology and therapeutic frontiers

Chikungunya virus (CHIKV), a re-emerging mosquito-borne alphavirus, has transitioned from an endemic pathogen to a global public health threat. In May 2026, the World Health Organization’s second rapid risk assessment classified the global public health risk of CHIKV transmission as moderate. Although two vaccines (IXCHIQ ® and VIMKUNYA ® ) have been authorized in selected countries, no antiviral therapy has been approved, and supportive care remains the mainstay of clinical management. We synthesize current knowledge of CHIKV epidemiology, replication, host immune signaling, and immune evasion, together with the developmental landscape of vaccines and antivirals. Through a critical appraisal of available evidence, we propose a hierarchical evidence-weighting framework that distinguishes in vivo mechanistic findings, cell-line observations, and human validation, and we highlight the stage-dependent functions of cytokines. Finally, we outline unresolved questions in chronicity, antiviral development, next-generation vaccine design and optimization, and cross-regional public health coordination, with particular emphasis on bridging the evidence gap between animal models and human infection.