Trader consensus on Polymarket implies a 75.5% probability that the CDC will issue a Level 3 Travel Health Notice—recommending travelers reconsider nonessential trips due to outbreak risks—by December 31, 2026, driven primarily by the early May hantavirus cluster aboard the MV Hondius cruise ship in the South Atlantic, where Andes virus caused at least three deaths among passengers, prompting CDC Emergency Operations Center activation at its lowest Level 3 tier on May 7. No Level 3 notices are active per CDC's latest update, but multiple Level 2 alerts for meningococcal disease in the Democratic Republic of the Congo, global poliovirus circulation in over 30 countries, and clade II mpox in Ghana and Liberia signal escalation potential amid seasonal upticks in mosquito-borne illnesses like chikungunya and yellow fever. Ongoing surveillance by CDC and WHO, including passenger monitoring and genomic sequencing, will inform future notices, with historical patterns showing Level 3 activations during multi-country clusters.