Chikungunya virus: global epidemiology, transmission dynamics, and emerging challenges for public health.

During the last twenty years, Chikungunya virus (CHIKV), an arthropod-borne alphavirus, has resurged globally and emerged as an important public health concern. Driven by viral adaptive mutations, rapid urbanization, climate change, and the global expansion of Aedes mosquito habitats, CHIKV has continuously expanded its geographic distribution and triggered recurrent outbreaks across multiple continents. In this review, we comprehensively synthesize recent progress in virology, epidemiology, vector biology, diagnostic innovations, and vaccine research, emphasizing the integrated mechanisms that support its continued worldwide spread. Available data suggest that variation in vector competence, viral evolutionary adaptations (e.g., the E1-A226V mutation), and climatic-ecological shifts are key determinants of CHIKV transmission dynamics. Despite the approval of two vaccines, questions persist concerning their long-term safety profile, sustained immunogenicity, economic viability, and fair access in low-resource regions. Furthermore, substantial clinical overlap with dengue and Zika virus infections poses challenges to accurate diagnosis and epidemiological surveillance. It is essential to reinforce genomic and comprehensive vector surveillance and to develop cross-disciplinary risk prediction platforms within a "One Health" framework to improve global preparedness and response capacity. The establishment of data-informed, cooperative prevention strategies remains crucial for reducing the worldwide burden of CHIKV and other comparable arboviral diseases.