Chikungunya Vaccines in Travel Medicine: From Regulatory Approval to Real-World Challenges

Abstract

Background: Chikungunya virus (CHIKV) infection is an emerging disease of growing concern to international travelers due to the expanding geographic distribution of competent vectors, climate change, and frequent outbreaks in endemic and previously unaffected regions. Until recently, prevention relied exclusively on vector control and bite prevention; however, the recent approval of chikungunya vaccines has introduced a new preventive strategy. Methods: We conducted a narrative review of currently licensed chikungunya vaccines and candidates in clinical development, focusing on immunogenicity, safety, regulatory status, and implications for travel medicine practice. Results: Two vaccines have recently received regulatory approval: the live-attenuated vaccine IXCHIQ® and the virus-like particle vaccine Vimkunya®. Both demonstrated high immunogenicity based on neutralizing antibody thresholds accepted as surrogate markers of protection. Post-marketing safety signals associated with IXCHIQ®, particularly in older adults, have led to divergent regulatory decisions between authorities. The indication of vaccination in national recommendations varies somewhat depending on age, duration of travel, and individual risk factors. Several additional vaccine platforms remain under investigation, although some candidates have been discontinued. Conclusions: The recent approval of chikungunya vaccines marks a significant milestone in the field of travel medicine. However, uncertainties regarding long-term protection, safety in specific populations, and optimal targeting of travelers remain. Individualized risk–benefit assessment is essential, and further data are needed to refine vaccination strategies for travelers and populations at risk.