Hantavirus Tracker

An international Andes virus cluster tied to the MV Hondius expedition cruise — 11 cases, three deaths, and hundreds of passengers and crew monitored — has provoked coordinated responses from CDC, PAHO and WHO, including U.S. post‑exposure quarantine and cross‑border contact tracing.

The dominant theme is travel‑associated spillover forcing rapid operational action even as mainland U.S. hantavirus burden remains rodent‑driven (883 cumulative HPS cases, recent Colorado death); agencies concur overall population risk is low but differ in tactical measures, so watch person‑to‑person transmission potential of Andes, surveillance and diagnostic capacity, clinician testing uptake, and logistics for evacuations/quarantine.

Tracking: hantavirus

Geography: United States, Four Corners region (US), New Mexico, Colorado, Arizona, North America, South America, Argentina, Chile, Bolivia, Brazil, Uruguay, Peru, China, South Korea, Russia, Scandinavia (Finland, Sweden, Norway), Europe, Asia

1. CDC responds to Andes virus cruise outbreak; two Americans quarantined

CDC is responding to a deadly hantavirus outbreak on a cruise ship in the Atlantic Ocean, first reported May 2, 2026.

U.S. health officials have identified the Andes virus as the cause; Andes virus can lead to hantavirus pulmonary syndrome (HPS), a severe and potentially deadly lung disease.

The Hill reports the Trump administration required two American passengers who were exposed to the hantavirus to remain in a special quarantine facility in Nebraska.

Taken together, the accounts indicate active federal involvement in both outbreak response and post-exposure quarantine measures.

Key facts:

- Outbreak reported May 2, 2026

- CDC responding to deadly hantavirus outbreak on cruise ship

- Outbreak occurred in the Atlantic Ocean

- Andes virus identified as the cause

- Andes virus can cause hantavirus pulmonary syndrome (HPS)

Why it matters: Federal agencies are actively engaged, signaling use of containment and quarantine in response to maritime exposure. This could prompt increased scrutiny of cruise travel operations, contact tracing, and interagency coordination.

Watch for CDC updates on case counts, exposed passengers, ship identity and itinerary, and any expanded quarantine or travel advisories.

CDCThehill

2. PAHO alerts rising hantavirus cases; cruise ship outbreak confirmed

134 confirmed HPS cases in Argentina in 2024, 62 in Chile, and 11 confirmed cases tied to the MV Hondius cruise ship, including three deaths.

PAHO issued an epidemiological alert noting the Andes virus predominates in the Southern Cone and can transmit person-to-person, and it described seasonal increases in late spring and summer when outdoor activities intersect rodent habitats.

WHO has confirmed nine MV Hondius cases as the Andes virus strain, while 147 passengers and crew from more than 20 countries remain under monitoring as the ship heads to Tenerife.

PAHO recommends strengthening surveillance, laboratory diagnostic capacity, and public awareness campaigns; it also emphasized early symptom recognition and immediate medical care.

Evacuated passengers were escorted in full-body protective gear and disinfected, highlighting operational and international coordination challenges for travel-associated hantavirus exposure and response.

Key facts:

- 134 confirmed HPS cases in Argentina in 2024

- 62 confirmed HPS cases in Chile in 2024

- 11 confirmed cases on MV Hondius, including three deaths

- Nine MV Hondius cases identified as Andes virus

- 147 passengers and crew under monitoring from more than 20 countries

Why it matters: The Andes virus' person-to-person transmission potential, combined with a cruise ship cluster, raises the risk of multi-jurisdictional chains that extend beyond rodent exposures and strain international coordination.

Public health authorities and travel hubs should prioritize surveillance, diagnostic capacity, traveler monitoring, and clear risk communication to detect further cases and manage cross-border spread.

Watch for additional case confirmations, further strain identification, and how national systems implement PAHO's recommendations; failure to scale surveillance and lab capacity could delay detection and complicate clinical and containment responses.

Hantavirusreports

3. CDC reports 883 U.S. HPS cases, alerts clinicians to testing

The Centers for Disease Control and Prevention has updated hantavirus pulmonary syndrome (HPS) surveillance: 883 cumulative U.S. cases have been reported across 36 states since the first recognized outbreak in the Four Corners region in 1993.

Sin Nombre virus remains the primary North American cause; most cases are in rural western states, with New Mexico, Colorado, Arizona and California reporting the highest numbers.

The U.S. case fatality rate is about 36 percent, no specific treatment or vaccine exists, and the CDC emphasizes prevention.

On May 19, 2026, the American Hospital Association reported the CDC informed clinicians about available testing for suspected hantavirus infection.

The CDC recommends sealing holes to prevent rodent entry, using traps, and safely cleaning rodent droppings with appropriate respiratory protection; it also notes early recognition and prompt supportive intensive-care can improve outcomes.

Key facts:

- 883 cumulative HPS cases in the United States since 1993

- Cases reported across 36 U.S. states

- Sin Nombre virus is primary North American HPS cause

- Highest case counts: New Mexico, Colorado, Arizona, California

- U.S. case fatality rate approximately 36%

Why it matters: The CDC’s updated totals and clinician notification on testing keep hantavirus visible to public health and clinical communities, reinforcing surveillance and diagnostic pathways.

Given a high case fatality rate and no specific therapy, wider clinician awareness of testing and continued emphasis on rodent-proofing and safe cleanup are central to reducing morbidity and ensuring timely supportive care; watch for changes in detected case counts after clinician testing uptake.

HantavirusreportsAha

4. Colorado Reports First Hantavirus Death Since 2024

Colorado health authorities reported the state's first confirmed hantavirus death since 2024, attributed to the locally endemic Sin Nombre strain.

Officials said preliminary evidence indicates the infection was acquired through local rodent exposure, that the risk to the general public remains low, and that the investigation is ongoing.

The state emphasized spring-cleaning and outdoor work increase encounters with rodent droppings, and Boulder County issued advisories about cleaning barns, outbuildings, and grain storage areas.

By contrast, the Andes strain recently infected at least 11 people aboard the cruise ship MV Hondius, killing three; Sin Nombre is not spread person-to-person.

Key facts:

- Colorado reported its first confirmed hantavirus death since 2024.

- Infection traced to the Sin Nombre strain endemic to Colorado.

- Sin Nombre hantavirus does not spread person-to-person.

- Preliminary evidence: infection acquired by local rodent exposure (Hope Shuler).

- Colorado recorded 121 hantavirus infections, 45 deaths, 1993–2023.

Why it matters: The case highlights seasonal exposure risk: spring cleaning and outdoor chores increase contact with rodent droppings, so public health messaging and rodent-control measures should be reinforced now.

Officials and clinicians should watch for additional local cases, updated advisories, and investigation findings; because Sin Nombre lacks documented person-to-person spread, the immediate public-health threat remains environmental rodent exposure rather than community transmission.

Gizmodo

5. Multi-country Andes virus cluster linked to cruise causes 11 cases, three deaths

11 cases, including three deaths, were reported as of 13 May 2026 linked to an expedition cruise ship and infection with Andes virus.

WHO convened a webinar on 20 May 2026, 13:00–14:00 CEST to present what is known about hantaviruses and the current multi‑country event, and to discuss public health implications.

The agency is coordinating the international response under the International Health Regulations (2005), providing information sharing, contact tracing support, and ongoing risk assessment.

Hantaviruses are rodent‑borne and in the Americas can cause hantavirus cardiopulmonary syndrome; Andes virus is notable for limited human‑to‑human transmission via close contact.

WHO currently assesses the overall risk to the general population as low but emphasizes that this event highlights the importance of preparedness, surveillance and clear risk communication.

The webinar featured WHO leads Maria Van Kerkhove, Diana Rojas Alvarez, and Boris Pavlin, alongside country perspectives from Spain and behavioural insights from the UK.

Key facts:

- 11 cases reported as of 13 May 2026

- Three deaths among the 11 cases

- Event linked to an expedition cruise ship

- Andes virus implicated in the cluster

- Andes virus can transmit limited human‑to‑human via close contact

Why it matters: Because the cluster involves an expedition cruise and Andes virus with documented limited human‑to‑human spread, rapid international information sharing and contact tracing are immediate priorities under WHO coordination.

Monitor case counts, deaths, country reports, surveillance guidance, and risk communication; overall population risk is low but preparedness, targeted surveillance, and clear public messaging should be maintained.

World Health Organization