Hantavirus Explained: Symptoms, Risks, Death Rate & How to Protect Yourself (2026 Update)

What Is Hantavirus?

Hantaviruses are a family of viruses naturally carried by certain rodents - mainly mice and rats. People become infected primarily by breathing in tiny airborne particles from the urine, droppings, saliva, or nesting materials of infected rodents. This typically happens in enclosed, dusty places where rodents have been active: sheds, cabins, basements, barns, crawl spaces, and warehouses.

The virus can also enter the body through:

• A bite or scratch from an infected rodent (rare)
• Contaminated material touching the eyes, nose, or mouth
• Cuts or open wounds that come into contact with rodent excretions

According to the WHO, an estimated 10,000 to over 100,000 hantavirus infections occur worldwide each year, with the largest disease burden in Asia and Europe.

What Diseases Does Hantavirus Cause?

Hantaviruses cause two main illnesses, depending on the virus strain and geographic region.

1. Hantavirus Pulmonary Syndrome (HPS) - also called HCPS

• Found mainly in the Americas (North, Central, and South America)
• Attacks the lungs, leading to fluid build-up and severe breathing problems
• Can progress from flu-like symptoms to respiratory failure within days
• The most common U.S. strain is the Sin Nombre virus, carried by the deer mouse
• The Andes virus, found in Argentina and Chile, is the only hantavirus known to spread from person to person

2. Hemorrhagic Fever with Renal Syndrome (HFRS)

• Common in Asia and Europe
• Affects the kidneys and blood vessels
• Caused by strains such as Hantaan, Dobrava, Seoul, Puumala, and Saaremaa viruses
• The Seoul virus is found worldwide, including in the United States, often associated with city rats

There is also a milder form, called non-pulmonary hantavirus infection, which causes flu-like symptoms without the severe lung or kidney complications.

What Are the Symptoms of Hantavirus?

Hantavirus symptoms develop in two distinct stages. Crucially, early symptoms can look identical to the flu, which is one reason the disease is often missed in its earliest, most treatable phase.

Early Symptoms (1–8 weeks after exposure)

• Fever and chills
• Severe muscle aches (especially in the thighs, hips, back, and shoulders)
• Headache
• Fatigue
• Nausea, vomiting, diarrhea, or abdominal pain
• Dizziness

About half of all infected people also develop gastrointestinal symptoms during this phase.

Severe / Late Symptoms (4–10 days after early symptoms)

• Coughing
• Shortness of breath
• Chest tightness as the lungs fill with fluid
• Low blood pressure (shock)
• Kidney failure (in HFRS cases)

For the Andes virus specifically, symptoms generally appear 4 to 42 days after exposure, and the disease can progress very rapidly once severe symptoms begin.

How Deadly Is Hantavirus? (Case Fatality Rate)

The case fatality rate varies significantly by strain and region. Here's what the WHO and CDC report:

For context, the CDC reports that since U.S. surveillance began in 1993, 890 hantavirus cases had been documented through the end of 2023 - making it rare but consistently severe when it does occur.

Is Hantavirus Spreading Right Now? (May 2026 Update)

Yes. As of early May 2026, an outbreak of hantavirus is being investigated in connection with the Dutch-flagged expedition cruise ship MV Hondius, which had departed from Ushuaia, Argentina. The WHO was first notified on May 2, 2026, after a cluster of severe respiratory illness was identified among passengers.

Current outbreak facts

• Cases: As of May 8, 2026, the WHO reports approximately 8 suspected and 5 confirmed cases, with some news outlets reporting slightly higher numbers
• Deaths: 3 reported fatalities so far among passengers
• Strain involved: The Andes virus (the only hantavirus capable of limited person-to-person transmission)
• Likely source: The presumed index case - a Dutch passenger - is believed to have been exposed in South America before boarding the ship, after a four-month trip through Chile, Uruguay, and Argentina

Countries affected

Passengers from at least 12 countries were aboard the MV Hondius, including the United States, Canada, the United Kingdom, the Netherlands, Switzerland, Germany, and Spain. Some passengers disembarked at Saint Helena (a British overseas territory) on April 24, prompting international contact tracing. Health authorities in South Africa, Spain, Switzerland, the Netherlands, and the United States have all been involved in the response.

Is this another COVID-19?

No. WHO officials, including epidemiologist Dr. Maria Van Kerkhove, have explicitly stated that hantavirus does not behave like COVID-19. It does not transmit efficiently through casual respiratory contact. Even the Andes strain - the only one that can spread person-to-person - accounts for only an estimated 2% to 5% of cases through human transmission, and that spread is generally limited to very close, prolonged contact (such as caregivers or sexual partners).

The CDC's acting director has stated that the risk to the U.S. public is "very low," and the WHO's current global risk assessment is also low.

How Can You Protect Yourself From Hantavirus?

Because hantavirus is rodent-borne, rodent control and avoidance are the most important prevention strategies. The CDC recommends the following measures:

Around your home

• Seal entry points. Close any gaps or holes larger than ¼ inch with steel wool, caulk, or hardware cloth - especially around pipes, vents, and foundations
• Set traps in and around the home if rodents are present
• Store food securely in sealed containers, including pet food
• Eliminate nesting sites by clearing brush, woodpiles, and clutter near the home

When cleaning rodent-infested areas

• Do not sweep or vacuum dry droppings - this aerosolizes the virus
• Ventilate the area for at least 30 minutes before cleaning
• Wear rubber or latex gloves and an N95 respirator mask if cleaning heavy infestations
• Spray droppings, nests, or dead rodents with a disinfectant or a 1:10 bleach-and-water solution and let it soak for at least 5 minutes before wiping up with paper towels
• Double-bag waste in sealed plastic bags before disposal
• Wash hands thoroughly after removing gloves

When traveling

• Avoid sleeping in rodent-infested cabins, sheds, or rural shelters
• In South America (especially Argentina and Chile), avoid contact with wild rodents and dusty enclosed spaces
• After returning from travel, monitor yourself for flu-like symptoms for up to 6 weeks and seek medical care immediately if they appear, mentioning your travel history

Is There a Treatment or Vaccine for Hantavirus?

Currently, there is no specific antiviral treatment and no licensed vaccine for hantavirus infection approved for use in most countries. (China and South Korea have developed vaccines for HFRS strains used regionally.)

Treatment is supportive and focuses on:

• Early hospitalization, ideally in an Intensive Care Unit (ICU)
• Oxygen support and, in severe cases, mechanical ventilation
• IV fluids and blood pressure management
• Dialysis for kidney failure (in HFRS cases)
• Extracorporeal membrane oxygenation (ECMO) in critical lung failure cases

Early medical attention dramatically improves survival. This is why the CDC stresses that anyone with flu-like symptoms following potential rodent exposure - or recent travel to an outbreak area - should seek medical care promptly and tell their physician about the possible exposure.

When Should You See a Doctor?

Contact a healthcare provider immediately if you experience flu-like symptoms (especially fever, deep muscle aches, and shortness of breath) AND any of the following apply:

• You have been around rodents, droppings, or rodent-infested buildings recently
• You have cleaned a cabin, shed, basement, or other enclosed space where rodents may have been active
• You have recently traveled to South America, especially Argentina or Chile
• You have had close contact with someone confirmed to have hantavirus

Be sure to tell your doctor about possible rodent exposure or relevant travel. Hantavirus is easy to miss in early stages because the symptoms mimic seasonal flu.

Should You Panic About Hantavirus?

No - but awareness matters. Here's why public health experts are urging calm:

• The virus is rare - only a few hundred cases occur annually in the Americas
• It is not easily spread between people, and only one strain (Andes) is even capable of person-to-person transmission
• Outbreaks are being closely monitored by the WHO, CDC, and national health authorities
• There is no evidence of widespread community transmission anywhere in the world
• The current outbreak appears to be a contained event linked to a single ship and traceable contacts

The most important things you can do are practice good rodent prevention at home, seek medical care early if you have symptoms after possible exposure, and stay informed through reliable sources.

Frequently Asked Questions About Hantavirus