Hantavirus Global Situational Briefing — May 15, 2026

The French patient at Hôpital Bichat remains on ECMO with no reported change in condition. Dr. Stephen Kornfeld's confirmatory PCR came back negative, clearing the US of any confirmed Andes virus (ANDV) cases. CDC has now disclosed a total of 41 people under monitoring across 16 states. A fifth Californian exposure — via a connecting flight rather than the ship itself — has been located in the remote Pitcairn Islands. MV Hondius is 48–72 hours from Rotterdam.

This briefing covers the delta window 2026-05-14 01:00 UTC+8 → 2026-05-15 00:00 UTC+8.

Cluster overview: 11 cases, 3 deaths — count unchanged

The MV Hondius Andes hantavirus cluster stands at 11 total cases — 8 laboratory-confirmed, 2 probable, 1 inconclusive — with 3 deaths and a case fatality ratio of 27%. 1 ECDC's daily monitoring page, updated May 14 at 12:00 CET, records no new cases or deaths since the previous update. 1 The most recent WHO Disease Outbreak News remains DON-601 (May 13); no DON-602 has been issued as of the close of this reporting window. 2

The dominant developments in this 24-hour window are not fresh case additions but status revisions: the US inconclusive case has resolved toward negative, Spain's previously asymptomatic patient has developed clinical symptoms while remaining stable, and France has cleared all 26 contacts — each shifting the cluster's downstream risk profile.

France: ECMO patient unchanged; all 26 contacts PCR-negative

The 65-year-old French woman at Hôpital Bichat-Claude Bernard in Paris continues on extracorporeal membrane oxygenation (ECMO). Her condition is described as the "final stage of supportive care" by infectious disease specialist Dr. Xavier Lescure at Bichat — a circuit that substitutes for both cardiac and pulmonary function when those organs cannot maintain adequate perfusion independently. 3 No change in her clinical trajectory was reported in the 24 hours ending at the close of this window.

French Health Minister Stéphanie Rist announced that all 26 contacts traced from the patient's infection chain tested PCR-negative. The group includes 22 contacts traced from the repatriation flight and 4 Bichat hospital returnees. 3 Rist stated it is "now possible to rule out any earlier contamination of other people at this stage of the scientific work." 3 Surveillance continues at three PCR tests per week, coordinated by Santé publique France, INSERM, and ANRS MIE; future notifications will issue only on a positive result.

A new preprint posted May 14 to Preprints.org (Lee & Hasan, University of Barcelona / Stanford) reports VA-ECMO survival rates approaching 80% in experienced centers when initiated at first signs of cardiopulmonary decompensation — cardiac index below 2.2 L/min/m² or plasma lactate above 4.0 mmol/L. 4 The review has not been peer-reviewed.

French wholesale demand for FFP2 respirator masks increased approximately fivefold in one week: one distributor moved from 2,400 boxes per week to 15,000 boxes over three days, and the three wholesalers controlling roughly 95% of the French market have flagged limited availability. 3

United States: Kornfeld PCR-negative; 41 under monitoring; fifth Californian located in Pitcairn Islands

Dr. Stephen Kornfeld, the 69-year-old Oregon-based retired oncologist who served as the ship's physician during the acute phase of the Hondius outbreak, has received a confirmatory PCR result: negative. 5 He has been transferred out of the biocontainment unit at the University of Nebraska Medical Center (UNMC) into standard quarantine alongside 15 other US passengers. 5 A serology (antibody) test remains pending; that result will determine whether he was ever infected. None of the 16 facility-quarantined US passengers are symptomatic.

Kornfeld reflected on the ambiguity in a CNN interview: "At the time, it was felt like this is just some virus. And now, in retrospect, there is a question, could it have been hantavirus? But it's just speculation. There's no way to really know." 5 CDC Incident Manager Dr. David Fitter described his original result as "inconclusive" — one positive from one laboratory, one negative from a second. 6 With the confirmatory PCR negative, CDC has stated there are currently zero confirmed hantavirus cases in the United States.

CDC this week disclosed the first precise figure for US monitoring: 41 people across 16 states. 7 The population divides into three groups: 18 in facility quarantine in Nebraska or Atlanta; approximately 23 monitoring at home; and flight passengers exposed while traveling on the same aircraft as a symptomatic confirmed case. 8 The 42-day window runs from May 11 through June 22. 6 Dr. Fitter reiterated: "Currently, there are no state or federal quarantine orders that have been drawn." 6

A fifth California resident with Hondius exposure was confirmed by the California Department of Public Health (CDPH). 9 Unlike the other California cases, this individual — a Sacramento County resident — was not aboard the vessel; exposure occurred on an international flight that carried a passenger who later died from ANDV. The person departed California for travel before the outbreak was publicly identified and is currently in the Pitcairn Islands (a British Overseas Territory in the South Pacific), under joint monitoring by CDC and UK health officials. 9 All five California-resident exposures remain asymptomatic.

Separately, the Illinois Department of Public Health (IDPH) continues to investigate a possible hantavirus case in Winnebago County with no connection to MV Hondius. 10 The patient is believed to have acquired a North American strain while cleaning a residence with rodent droppings; symptoms were mild and did not require hospitalization. Commercial serology tests returned positive, but CDC treats those as non-definitive; CDC confirmatory testing may take up to 10 days. IDPH noted: "Unlike the Andes strain of Hantavirus responsible for the cruise outbreak, the North American strains are not known to spread from person-to-person." 10

Spain: first symptoms, condition stable

Spain's confirmed ANDV patient — a 70-year-old male at the Hospital Central de la Defensa Gómez Ulla in Madrid's UATAN high-isolation unit — has developed respiratory symptoms including fever and shortness of breath. 11 This represents clinical progression since the last reporting cycle, when the patient was described as asymptomatic following repatriation. His condition is nonetheless assessed as stable.

"Continúa estable, es la mejor de las noticias que se pueden tener y esperamos que se mantengan."
"He remains stable — that is the best possible news one can have, and we hope it continues." — Javier Padilla, Spain's Secretary of State for Health 11

Padilla also cautioned that "there is still a need to be prudent in predicting the course of infectious diseases." 11 A new isolation protocol takes effect when the patient completes one week in quarantine — approximately May 17–18 — at which point a negative PCR result will allow supervised visits and limited supervised movement within the facility. The 13 other Spanish passengers quarantined at Gómez Ulla are reported in fair condition. The 26 Dutch returnees repatriated via the Netherlands' National Institute for Public Health and the Environment (RIVM) have all returned negative PCR results. 11

MV Hondius and international repatriations

MV Hondius remains at sea, carrying 25 crew members and 2 RIVM public health workers, with a projected Rotterdam arrival of May 17–18. No crew members are symptomatic. Disinfection protocols are being finalized with RIVM.

Five Australian citizens and one New Zealand citizen, all PCR-negative and asymptomatic, landed at RAAF Base Pearce near Perth this morning after a repatriation charter from the Netherlands. 12 The group transferred to the Bullsbrook Centre for National Resilience — a 500-bed quarantine facility 40 km northeast of Perth — where they will be isolated for at least three weeks before assessment of whether the full 42-day window requires facility-based completion. Australian Health Minister Mark Butler confirmed: "There is a PCR test for hantavirus, and they have tested negative. I can also indicate they are all symptom-free." 12 Butler characterized the approach as "the strongest response of any country accepting passengers from this cruise ship." 12

WHO and ECDC guidance updates

No new WHO Disease Outbreak News has been issued since DON-601. ECDC published three documents on May 14 alongside its routine daily monitoring update: 13

Laboratory testing guidance for high-risk ANDV contacts, including a decision tree, PCR testing trade-off analysis, and a testing strategy for asymptomatic contacts 13
Recording of the May 13 Stockholm press conference covering epidemiology, repatriations, infection control, and transmission investigation 14
FAQ slide deck on hantavirus disease (3.22 MB) 1

Risk to the general EU/EEA population is maintained at very low.

Finland expanded its legal toolkit on May 11, when the Orpo government amended its infectious disease decree to classify Andes virus as a yleisvaarallinen tartuntatauti — a "generally dangerous infectious disease." 15 The classification activates statutory quarantine authority and entitles quarantined persons to infectious disease daily allowance. Social Security Minister Sanni Grahn-Laasonen described the measure as precautionary: "The amendment is needed so that authorities have the tools under the Communicable Diseases Act to prevent a possible spread in Finland." 15 Two Finnish travelers exposed on the Johannesburg–Amsterdam flight of April 25 are in 42-day quarantine; no infections have been detected in Finland.

Americas endemic surveillance

Argentina — Argentina's Boletín Epidemiológico Nacional for SE17 (published May 13) holds the 2025–26 season total at 102 confirmed cases and 32 deaths (CFR 31.4%), with only one new case reported in the past two weeks, from Buenos Aires province. 16 Genomic sequencing by Argentina's reference laboratory ANLIS Malbrán determined that the cruise cluster strain shows high similarity to strains detected in Neuquén province in 2018. 16 The outbreak's geographic origin remains unresolved: Argentina's Ministry of Health stated the index case "did not visit endemic Andes-strain zones during the estimated infection window," leaving the spillover site unconfirmed. 16 BEN SE18 is expected around May 19.

Brazil — The health secretariat of Brasília's Distrito Federal is monitoring 3 suspect hantavirus cases, all with symptom onset in April 2026. 17 None are confirmed as of May 14. The DF had recorded no hantavirus cases for the three prior years; since 2013 the region has accumulated 20 confirmed cases and 14 deaths (CFR 70%, above the national average). Brazil's national 2026 year-to-date figure stands at 7–8 confirmed cases and 2 deaths. Rio Grande do Sul has 2 confirmed 2026 cases, including the death in Paulo Bento under clinical-epidemiological confirmation pending Fiocruz laboratory verification. 18 Brazil's cumulative 2013–May 2026 total is 860 cases and 341 deaths (CFR 39.7%). 19

Chile — National figures hold at 39 confirmed cases and 13 deaths (CFR 33%) through early May. 20 Aysén Region's health secretariat issued a cold-season alert on May 12: falling temperatures are reducing wild rodent food sources, driving animals closer to human dwellings. 20 The region's third 2026 case — a 66-year-old male agricultural worker from Lago Atravesado, Coyhaique — remains in a Santiago hospital on mechanical ventilation.

ENSO outlook — NOAA's Climate Prediction Center issued an El Niño Watch on May 14, raising the probability of El Niño conditions emerging between May and July 2026 from 61% (April forecast) to 82%, with a 96% probability of continuation through December 2026 – February 2027. 21 El Niño events have historically been associated with expanded rodent populations in the Southern Cone, a recognized precursor to elevated HPS incidence. NOAA noted that "while confidence in the occurrence of El Niño has increased since last month, there is still substantial uncertainty in the peak strength." 21 The next ENSO Diagnostic Discussion is scheduled for June 11.

Research and pipeline

Two preprints bearing direct clinical relevance appeared this week.

A May 14 submission to Preprints.org by Lee (University of Barcelona) and Hasan (Stanford) reviews HPS cardiopulmonary failure and ECMO-based management, identifying three pathological axes: VEGFR2-mediated microvascular permeability, CD8+ T-cell immunopathology, and direct hantaviral myocarditis. 4 VA-ECMO survival rates approach 80% in experienced centers when initiated before circulatory collapse; no antiviral has demonstrated efficacy during the cardiopulmonary phase in controlled trials. 4

A May 12 bioRxiv preprint by Tomczak and Weglarz-Tomczak (Nature Innovation Laboratory) used molecular docking to identify six protease inhibitor compounds targeting host endoplasmic reticulum enzymes Signal Peptidase (SP) and Signal Peptide Peptidase (SPP) — proteins required for hantavirus glycoprotein maturation. 22 Compound E achieved the highest binding score against SPP. The authors flag that "experimental validation" remains outstanding. 22 This is a computational study only; no in vitro or animal data exist yet.

South Africa's National Institute of Communicable Diseases (NICD) deposited the first South African ANDV sequences to Pathoplexus (accessions PP_006WDJK.1, collection May 2; PP_006WDKH.1, collection April 26). 23 The database now holds 505 sequences. All Hondius cluster sequences remain within ≤1 SNP of each other, consistent with a single zoonotic introduction and subsequent human-to-human spread. 23

Traws Pharma (NASDAQ: TRAW) filed an SEC S-3 shelf registration for resale of up to 35.9 million shares. 24 The company's May 8 press release confirmed a hantavirus antiviral program drawing on its existing negative-strand RNA virus library. CMO Robert Redfield (former CDC Director) called for "an emergency program to develop life-saving treatments for this extremely dangerous disease and to enable stockpiling for emergent outbreaks and National Security concerns." 24 No specific compound name, mechanism, or clinical timeline has been disclosed. Q4 2025 earnings are expected May 18.

Claims that vandetanib (a VEGFR2 inhibitor) represents a new 2026 treatment advance trace to a 2016 hamster-model study (Bird et al., Antiviral Research, PMID 27233645); no new vandetanib hantavirus data appeared in 2026. 3 Moderna's mRNA hantavirus vaccine, developed with Korea University, remains preclinical with no Phase 1 trial initiated. 25

Watchlist for May 16

French patient at Bichat: The ECMO circuit is the ceiling of available hemodynamic-pulmonary support. AP-HP has not issued a clinical update; next scheduled monitoring update from Santé publique France is expected within 24–48 hours.
Dr. Kornfeld antibody test: PCR is negative; serology will determine whether prior infection occurred during the voyage.
Illinois Winnebago County case: CDC confirmatory testing result expected around May 22. If confirmed, it would be the eighth hantavirus case in Illinois since 1993.
MV Hondius Rotterdam arrival: ETA May 17–18; RIVM disinfection and crew testing outcomes to follow.
Argentina origin investigation: ANLIS Malbrán has established genetic proximity to a 2018 Neuquén strain; field investigation of the index case's itinerary continues.
ENSO trajectory: No new NOAA update until June 11. Southern Cone public health authorities should factor the 96% El Niño persistence probability into winter rodent monitoring plans now.

Briefing covers 2026-05-14 01:00 UTC+8 → 2026-05-15 00:00 UTC+8. Previous edition: Hantavirus Global Situational Briefing — May 14, 2026. Next scheduled publication: May 16, 2026.

Cover image: ECMO machine circuit in a high-contrast ICU setting — AI-generated.