The World Health Organization announced on Wednesday that it will declare the hantavirus outbreak linked to the Dutch-flagged cruise ship MV Hondius officially over on 2 July, provided no further infections are detected among the 54 people still in quarantine. The milestone would close a six-week international monitoring effort that traced more than 650 contacts across 33 countries and territories, following 12 confirmed and one probable case of the Andes virus, three of them fatal. Director-General Tedros Adhanom Ghebreyesus told a Geneva press briefing that all but the final cohort had completed their 42-day observation period, the maximum incubation window for the only hantavirus strain known to transmit between humans.

The outbreak began aboard the expedition vessel after it departed Ushuaia, Argentina, on 1 April, sailing via remote South Atlantic islands towards Cape Verde and eventually Tenerife, where remaining passengers were evacuated. The Andes variant, endemic to rodent populations in southern Argentina and Chile, typically spreads through contact with contaminated urine or droppings, but can pass from person to person in conditions of close proximity—a pattern that matched transmission between cabin-mates on the ship. With no specific treatment or vaccine, the virus carries a case fatality rate that can reach 50 percent, depending on access to intensive care.

Viewed from Washington, the US Department of Health and Human Services confirmed that all 18 Americans who had been placed in a specialised quarantine unit in Nebraska, along with seven monitored at home, have now been released. Secretary Robert F. Kennedy Jr. credited the coordinated response for preventing any domestic transmission, though some passengers described the mandatory isolation as overly restrictive. In Ottawa, Health Canada reported that 34 citizens completed self-isolation, with the sole Canadian case having recovered by 9 June. Spanish authorities, praised by Tedros for their leadership, managed the ship’s exceptional anchorage off Tenerife under a maritime exclusion zone to prevent port-side exposure.

With the public-health phase winding down, the WHO is now shifting to the scientific agenda. Samples collected aboard the Hondius will be shared with the organisation’s BioHub in Switzerland, a step that Geneva-based officials say is critical for developing diagnostics, treatments and vaccines for future outbreaks. An epidemiological study of exposed individuals is also under way to better characterise the disease’s progression. The 2 July date remains contingent on no new cases surfacing among the last contacts, a threshold that will formally end an episode that tested global health-security protocols in an era of high-mobility travel.