Trader consensus on Polymarket reflects near-certainty at 99.4% for no Nipah virus cases in the US by March 31, driven by the virus's strict geographic confinement to South and Southeast Asia—primarily Bangladesh and India—where fruit bats serve as the natural reservoir, with no history of endemic transmission or even imported human cases in the United States per CDC records. Recent WHO surveillance confirms ongoing seasonal clusters in Bangladesh, but global incidence remains low at under 100 suspected cases annually, with effective airport screenings, contact tracing, and a 4–14 day incubation period enabling detection. Realistic shifts could arise from an undetected traveler during peak transmission (May–June or November–December) evading border controls, though robust public health infrastructure and absence of amplifying hosts like pigs in the US make this improbable; next CDC/WHO updates expected routinely.