Transmission-Blocking SFTS Vaccines for Companion Animals from One Health Perspective: Development Status and Challenges for Commercialization (Review)
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis whose public health risk is increasingly shaped by an expanding “tick–companion animal–human” transmission cycle. This study aimed to frame vaccination of companion animals as a One Health, transmission-blocking intervention and to identify the scientific and product-development bottlenecks that have delayed commercialization. We conducted (i) a structured narrative review of preclinical SFTS vaccine candidates across major platforms, including DNA vaccines, viral-vectored vaccines, live-attenuated vaccines, recombinant protein vaccines, lipid nanoparticle (LNP)-mRNA vaccines, and replicating RNA vaccines, and (ii) a cross-sectional survey of pet owners to assess disease awareness and vaccine acceptance. The survey revealed a clear implementation gap: while most respondents reported low awareness of SFTS, willingness to vaccinate companion animals was comparatively high, indicating substantial unmet demand. Across platforms, preclinical studies demonstrate protective efficacy, but practical translation is constrained by platform-specific barriers such as device-dependent delivery, biosafety concerns, limitations in inducing sterilizing immunity, and challenges in formulation stability, cold-chain logistics, and scalable manufacturing. We propose that target product profiles for veterinary SFTS vaccines should prioritize reduction or elimination of viremia and viral shedding as primary endpoints, rather than survival alone, to effectively interrupt spillover risk. Advancing candidates that meet these transmission-blocking criteria while resolving deployment and manufacturing constraints will be critical to achieving commercialization and establishing a durable immune barrier in companion animals