Hantavirus exposure checklist

What to do if you may have been exposed — written from CDC, WHO, and PAHO guidance. Not medical advice. Last reviewed May 2026.

TL;DR

If you had recent close contact with rodents (or their droppings/urine), spent time in an enclosed space with rodent activity, or were on the MV Hondius cruise: watch for fever + severe muscle aches in the next 1 to 8 weeks. If those develop and especially if shortness of breath follows, seek medical care immediately — tell the doctor about your exposure. There is no vaccine and no specific antiviral cure; early supportive care is what changes the outcome.

Step 1 · Right now

Document the exposure

  • Write down the date, place, and nature of the suspected exposure (rodent contact, building with droppings, travel itinerary, contact with a confirmed case).
  • Save your travel records. If you were on the MV Hondius cruise, keep your booking confirmation, boarding pass, and any health authority contact information you received on disembarkation.
  • Note the exact date you started feeling unwell if symptoms appear later — it helps clinicians and contact tracers.
Step 2 · Self-monitor

Watch for early symptoms for 8 weeks

The CDC says signs of HPS typically appear 1 to 5 weeks after exposure, but can range up to 8 weeks. For Andes virus specifically — the strain in the 2026 MV Hondius cluster — the window is 4 to 42 days after exposure.

Early (prodromal-phase) symptoms — track any of these:

  • Fever (often the first sign)
  • Severe muscle aches — especially in the thighs, hips, back, and shoulders
  • Headache
  • Dizziness, chills
  • Nausea, vomiting, abdominal pain, or diarrhoea

These resemble common viral illnesses, which is exactly why CDC notes HPS is difficult to diagnose at onset. Mention your exposure history to whichever clinician you see.

Step 3 · Emergency

Seek care immediately if breathing changes

The cardiopulmonary phase begins 4 to 10 days after the initial fever. Per WHO, symptoms include sudden onset of respiratory distress and hypotension (low blood pressure). Fluid fills the lungs.

Call emergency services if you experience any of these:
  • Shortness of breath or rapid breathing
  • Tightness in the chest, feeling unable to get air
  • Coughing (sometimes with frothy or pink-tinged fluid)
  • Lightheadedness or fainting
  • Rapid heart rate

Tell paramedics and the receiving hospital about your exposure history immediately. WHO emphasises that early supportive medical care is key to improve survival — the window between presentation and ICU admission matters.

Step 4 · Reporting

Tell your country's health authority

Hantavirus infection is a notifiable disease in most jurisdictions. Your doctor will typically file a notification for you if you test positive — but if you have a confirmed exposure and are not yet symptomatic, the relevant authority may want to add you to their monitoring list. Direct numbers:

Step 5 · Reduce further risk

Avoid spreading the situation

Person-to-person transmission of hantavirus is very rare overall, but Andes virus is the one exception. Per WHO, human-to-human transmission has been documented only for Andes virus in the Americas and remains uncommon. If your exposure was Andes-related (e.g. the MV Hondius cluster):

  • Limit close contact with household members during the monitoring window — particularly anyone immunocompromised, pregnant, or elderly.
  • Don't share towels, utensils, or bedding until cleared.
  • If symptoms appear, isolate at home until you can be evaluated.
Questions

Frequently asked

How long after exposure do hantavirus symptoms appear?

1 to 5 weeks typically, up to 8 weeks in some cases. For Andes virus specifically: 4 to 42 days (CDC).

What are the early symptoms of hantavirus pulmonary syndrome?

Fever, severe muscle aches (thighs/hips/back/shoulders), headache, nausea, vomiting, dizziness, chills, abdominal pain. These resemble many common illnesses, so HPS is difficult to diagnose at illness onset, per CDC.

When does hantavirus become life-threatening?

4 to 10 days after the initial fever, the cardiopulmonary phase begins: coughing, shortness of breath, lungs fill with fluid, blood pressure drops. WHO reports a case fatality rate of up to 50 percent in the Americas for hantaviruses; CDC reports approximately 4 in 10 (38 percent) for HPS overall.

Is there a vaccine or specific treatment?

No vaccine is approved in the US or EU; no antiviral cure. Per WHO, early supportive medical care is key to improve survival and focuses on close clinical monitoring and management of respiratory, cardiac and kidney complications. The earlier you present, the better the outcome.

Sources

References

This page is not medical advice. If you have a medical emergency, call your local emergency number.