Trader sentiment reflects a 75.5% implied probability for a CDC Level 3 Travel Health Notice by December 31, driven primarily by the early May hantavirus outbreak linked to the MV Hondius cruise ship, where Andes virus cases among passengers prompted CDC's Level 3 Emergency Operations Center activation and a Health Alert Network advisory. With confirmed cases dispersed across Cape Verde, Spain's Canary Islands, and U.S. states, hantavirus's up to 38% case-fatality rate and rare person-to-person potential in certain strains fuel escalation fears, despite no sustained transmission detected. No Level 3 notices exist currently—only Level 2 alerts for chikungunya in Mauritius (updated May 14), meningococcal disease, and global poliovirus—but persistent H5N1 human infections (71 U.S. cases since 2024) and measles upticks add pressure. Weekly FluView updates and surveillance data will clarify trajectories amid inherent outbreak uncertainties.