HAN

The CDC Health Alert Network (HAN) is the United States public health notification system used by the Centers for Disease Control and Prevention to communicate urgent health advisories, clinical guidance, and situational updates to healthcare providers, public health officials, and emergency responders across the country. HAN advisories are distributed through state and local health departments, hospitals, clinicians, and emergency management networks, and are publicly posted on the CDC website simultaneously.

The HAN system operates on four tiers of escalating urgency: Health Alert (highest — immediate action or attention); Health Advisory (important information for a specific incident or situation); Health Update (updated information on an ongoing situation); and Info Service (routine updates and resource links). The tier determines the recommended response timeline and the breadth of distribution across the health system.

HAN advisory HAN00528, issued on 8 May 2026, required airborne infection isolation precautions for all suspected Andes hantavirus patients in the United States — a higher infection-control tier than the standard droplet precautions applied to other hantaviruses. The advisory also noted that ECMO, if started early, can improve Andes survival to approximately 80%, and directed that US repatriates from the MV Hondius cluster be routed to the Nebraska specialist biocontainment facility. HAN00528 directly addressed the clinical guidance gap in the original WHO DON 599, which had applied standard hantavirus protocol rather than Andes-specific person-to-person transmission precautions.