CDC issued HAN00528 (Health Alert Network Advisory 00528) on 8 May, requiring airborne infection isolation for all suspected Andes hantavirus patients in the United States. 1 Airborne isolation requires negative-pressure rooms and N95 respirators; the original WHO DON 599 applied generic hantavirus droplet precautions: surgical masks and ordinary isolation rooms, with no negative-pressure requirement. The distinction is meaningful: all other hantaviruses are believed to spread only from rodents to humans; Andes virus is the only member of the family with documented person-to-person transmission, first recorded in the 1996 El Bolsón cluster in Patagonia.
CDC directed US repatriates from the MV Hondius cluster to the specialist biocontainment facility in Nebraska, one of a small number of US sites equipped with the negative-pressure capacity and clinical expertise for Andes management at scale. The advisory noted that ECMO (extracorporeal membrane oxygenation, a life-support technique that substitutes for heart and lung function in critically ill patients) can improve Andes survival to approximately 80% if initiated early. In practice, that figure is conditional on hospital capacity: outside academic medical centres, ECMO capacity is sparse, and the Nebraska routing reflects a deliberate concentration of specialist infrastructure.
The HAN00528 guidance resolves the clinical-protocol gap that existed between the original DON 599 and the Swiss Andes confirmation . From 2 May to 8 May, the six-day gap between the outbreak notification and the Andes-specific isolation advisory, healthcare providers caring for suspected MV Hondius cases in the United States were operating under droplet, not airborne, isolation requirements.
