No FDA-approved hantavirus vaccine is expected by December 2026, as reflected in the 94.5% market-implied probability for “No.” No orthohantavirus candidates have advanced beyond early Phase 1 or preclinical stages, with DNA and mRNA platforms targeting Gn-Gc glycoproteins showing only neutralizing antibody responses in limited human or animal testing. Low disease incidence, rodent-borne transmission, and the absence of Phase 3 efficacy trials for HPS or HFRS make timely licensure improbable under standard regulatory pathways. Recent 2026 outbreaks have prompted modest surveillance and funding increases from agencies like the CDC and WHO, yet these developments do not compress multi-year timelines. Accelerated approval or emergency use authorization remains theoretically possible but lacks precedent for this pathogen.