Hantavirus Global Situational Briefing — June 6, 2026

Day 11 without a new cluster case. The MV Hondius departed Rotterdam for Longyearbyen today, marking the vessel's physical exit from the outbreak zone it has occupied for three weeks. In Spain, the picture is less orderly: the second confirmed patient — hospitalised asymptomatic since May 25 — developed a low-grade fever in the past 24 hours, disrupting the expected discharge trajectory. France's ECMO patient enters her 30th day with no confirmed public update since May 28. Argentina has expanded the rodent origin investigation to Mendoza province, deploying a joint ANLIS–CDC team next week.

Today's departure caps a 19-day Rotterdam layover that began May 18. Oceanwide Expeditions confirmed on June 1 that, following the GGD Rotterdam clearance on May 30, the vessel would undergo its annual survey and scheduled maintenance before leaving for Longyearbyen on June 6; the first post-outbreak voyage is set for June 13 from Svalbard.1 The departure places the ship seven days transit ahead of its commercial restart. Twenty-five crew members and two RIVM medical staff who remained aboard for the decontamination quarantine period are no longer subject to Dutch public-health monitoring as of the vessel's departure; RIVM confirmed all tested PCR-negative throughout.

The cluster count remains at 13 cases — 11 laboratory-confirmed Andes virus, 2 probable — and 3 deaths. No death has been recorded since May 2; no new case since May 26. The WHO effective reproduction number estimate of Rt ≈ 0.7, published in DON 604 on May 28, remains the most recent official figure.2

Spain's second hantavirus patient — who had been asymptomatic at admission on May 25 — developed a low-grade fever (febrícula) in the hours preceding June 4, according to reporting by EFE, El Mundo, and Telemadrid.34 The patient, hospitalised at the UATAN isolation unit of Hospital Gómez Ulla in Madrid, had been expected to meet the discharge criteria — 3 symptom-free days plus 2 negative urine and oropharyngeal PCR results — around June 7, when the 28-day mandatory hospital phase for the asymptomatic contact cohort also lapses. The fever resets that clock.

Spain's first patient, the 70-year-old who was the initial confirmed case, was discharged from Gómez Ulla on approximately June 4–5, the first confirmed recovery in the cluster, with a 6-month follow-up protocol underway.5 The Spain Ministry of Health's June 4 discharge protocol — requiring 3 symptom-free days and 2 negative PCRs in urine and oropharyngeal exudate (Ct > 38) with blood PCR not mandated — applies to both cases. Post-discharge, patients face restrictions on blood contact until blood PCR clears, along with structured follow-up.

The 12 other Spanish evacuees at Gómez Ulla remain PCR-negative. Asymptomatic contacts in the 28-day hospital phase became eligible for home transition on approximately June 7 under the Spain Public Health Commission protocol.

The 65-year-old woman on extracorporeal membrane oxygenation at Hôpital Bichat AP-HP in Paris enters her 30th day on ECMO by June 6. The last public clinical update confirmed "no further deterioration as of May 28" — a nine-day window of official silence that gives no indication of trajectory. All 26 hospital-isolated contacts in France have returned PCR-negative on three-weekly testing; none has progressed to symptomatic disease. The patient received a supply of favipiravir tablets via the EC–Japan emergency procurement dispatched May 28.6

The CDC situation summary, last updated June 2, confirms 13 passengers remain at the National Quarantine Unit at the University of Nebraska Medical Center, with 5 having departed to complete home monitoring.7 Jake Rosmarin (Boston) has publicly committed to completing the full 42 days at the facility. State monitoring is active in Arizona, California, Oregon, and New York. The June 22 endpoint for the May 11 disembarkation cohort remains unchanged. No US resident has tested positive.

ECDC CDTR Week 23 (30 May – 5 June), published June 5, does not include a hantavirus section — the first issue since the outbreak began that omits the cluster from the weekly threat summary. The report covers Ebola (Bundibugyo, DRC/Uganda), West Nile virus, malaria, mpox, Dermatophilus congolensis, SARS-CoV-2 variants, MERS-CoV, and Salmonella Stanley.8 Its absence from the ECDC threat report does not reflect a formal de-escalation; the ECDC daily cluster update page remains live.

Argentina's Health Ministry announced on June 5 that ANLIS Malbrán scientists will travel to western Mendoza province to conduct joint rodent surveys with CDC experts from June 8 to 12, expanding the origin investigation beyond Tierra del Fuego.9 Sites were selected on "ecological and eco-epidemiological criteria" linked to rodent distribution patterns. The University of Mendoza noted the province has no confirmed local circulation of Andes virus but does have "a potential presence of the reservoir rodent."

Results from over 100 rodents trapped in Tierra del Fuego in May are still being processed in Buenos Aires; no date for release has been given. Mendoza is relevant because although hantavirus has not historically circulated there, the reservoir Oligoryzomys longicaudatus (the long-tailed pygmy rice rat) has a southern Andean distribution that could overlap with pre-boarding itinerary areas. Tierra del Fuego has never recorded a hantavirus case since reporting became mandatory 30 years ago, which makes the origin question scientifically open.

The Bariloche patient — a 45-year-old male in ICU at Ramón Carrillo Hospital, unrelated to the cruise ship cluster — has no public update as of this briefing. Argentina's 2026 domestic total remains at 47 confirmed cases nationally (EW20).9

The Lancet's June 6, 2026 issue — confirmed via @TheLancet on X — features a cover story tied to the ANDV outbreak; the journal noted "there is still no licensed vaccine for this strain."10 The specific article has not been publicly indexed at time of publication; the Lancet cover follows three cluster-related papers published online June 2–3, including the tocilizumab MEURI case series (4/5 treated vs. 0/5 untreated severe-HPS patients survived), two Lancet commentary/analysis pieces on the outbreak's surveillance lessons, and a Lancet Infectious Diseases commentary on the MV Hondius cruise ship deaths.