Hantavirus

Hantavirus refers to several related viruses that can cause life-threatening illness, including hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). The viruses are zoonotic, meaning that most of the time, you get them from animals. The most common way to get a hantavirus infection is by being around the pee, poop or saliva of infected mice or rats.

Hantavirus (pronounced “HON-tuh-vie-ruhs”) can look like other common illnesses at first. Symptoms can take one to seven weeks to appear and include fever, tiredness and muscle aches. But it can quickly get worse as it infects other parts of your body. Without quick treatment, it can cause serious illness and death. If you have flu-like symptoms after being around rodent nests or poop, it’s important to get help right away.

Hantavirus infections are rare. Between 1993 and 2023, there were 890 reported cases in the U.S.

Types

There are over 20 types of hantavirus. The most common types include:

• Andes virus: This spreads in areas of South America, especially Argentina and Chile. Once someone gets infected from rodents, the virus can spread to other people through close contact. Occasionally, this causes outbreaks of hantavirus, including one on a cruise ship in 2026. These are most often small and localized outbreaks.
• Sin Nombre virus: You can get Sin Nombre hantavirus from rodents in parts of North America. Most cases happen in western U.S. states. There’s no evidence that it spreads from person to person.
• Old World hantaviruses: You can get these hantaviruses from rodents in parts of Europe and Asia. They don’t spread from person to person.

Andes and Sin Nombre hantavirus can attack your lungs, causing severe breathing problems (hantavirus pulmonary syndrome or hantavirus cardiopulmonary syndrome). Old World hantaviruses can cause severe bleeding and kidney damage (hemorrhagic fever with renal syndrome).

Symptoms of hantavirus

Symptoms usually start within one to three weeks after exposure to hantavirus. They may include:

• Fever
• Chills
• Tiredness (fatigue)
• Muscle aches, especially around your thighs, hips and back
• Belly pain
• Nausea, vomiting or diarrhea
• Headache
• Dizziness

Four to 10 days later, if you develop hantavirus pulmonary syndrome, symptoms may include:

• Dry cough
• Trouble breathing
• Rapid heartbeat
• Chest tightness

Symptoms of hemorrhagic fever with renal syndrome start a week or two after exposure. They could include:

• Severe headaches
• Blood in your poop or pee
• Belly or lower back pain
• Flat, rash-like spots on your skin
• Eye redness
• Blurred vision
• Low blood pressure
• Peeing very little

Hantavirus infection causes

You can get hantavirus infections by breathing in particles of poop, pee and saliva from infected rodents. Rodents that can carry hantavirus include:

• Deer mice
• White-footed mice
• Rice rats
• Cotton rats
• Red-backed voles
• Bank voles

Hantaviruses can also spread through:

• Bites or scratches from an infected rodent
• Eating contaminated food
• Touching a contaminated surface and then touching your eyes, nose or mouth

Rarely, Andes virus can spread through close contact with someone who’s infected.

How hard is it to get hantavirus?

Most of the time, you have to breathe in contaminated dust or droplets of rodent pee, poop or saliva to get hantavirus. This means that sweeping, vacuuming or cleaning areas where mice or rats could have been (even if you can’t see them) increases your chance of getting it.

It’s difficult to say how easily hantavirus transmits from person to person since it’s so uncommon.

Risk factors

In the U.S., hantavirus infections are more common in states west of the Mississippi River. The highest numbers of reported cases have happened in Arizona, Colorado, California, New Mexico and Washington.

You’re more likely to get a hantavirus infection if you spend time in places where wild rodents live, especially if you disturb the dust and dirt. Mice and rats prefer rural environments — grassy or wooded areas with few buildings or people. But they may also make nests or forage in places like:

• Barns or grain silos
• Cabins
• Sheds
• Basements or attics

Complications

Hantavirus can attack your lungs, heart or kidneys. It can also weaken your blood vessels and make them leak. This can cause life-threatening illness, including:

• Acute respiratory distress syndrome (ARDS)
• Disseminated intravascular coagulation (DIC)
• Cardiogenic shock
• Organ failure

How doctors diagnose hantavirus

Your healthcare provider will ask about your symptoms and examine you. Make sure you tell them if you:

• Have had any recent contact with rodents or their droppings
• Live in or spend a lot of time in wooded areas
• Have noticed any signs of rodents around your home or place of employment
• Have a job or hobbies that could put you in contact with rodent pee or poop

Your provider will diagnose hantavirus with a blood test. They’ll send the blood sample to a lab for analysis and look for hantavirus antibodies or do PCR testing. They may also look for other signs, like:

• Larger-than-normal white blood cells
• Low platelet count
• Low oxygen levels

How is it treated?

Because a hantavirus infection can get worse very quickly, healthcare providers will most likely monitor and care for you in the hospital — even if your symptoms start out mild. If you have Andes virus, the hospital may need to take special precautions to prevent spreading the virus. Treatments for hantavirus may include:

• Oxygen therapy to get more oxygen into your body
• Mechanical ventilation to help you breathe
• IV fluids to keep you hydrated and balance electrolyte levels
• Vasopressors to raise your blood pressure
• Dialysis to filter your blood if your kidneys aren’t working
• ECMO (life support) to take over the work of your heart and/or lungs to help you recover

Treatment is supportive. Providers sometimes use the antiviral medication ribavirin for hemorrhagic fever with renal syndrome.

When should I see my healthcare provider?

Hantavirus can get worse quickly. If you develop hantavirus symptoms after contact with rodents, it’s important to get treatment as soon as possible. Call 911 or go to the nearest emergency room if you have:

• Fast heart rate
• Trouble breathing
• Blood in your pee, poop or vomit
• Weakness, lightheadedness or dizziness

What can I expect if I have hantavirus?

Hantavirus pulmonary syndrome is fatal in about 4 out of every 10 people who get it. Without treatment, most deaths happen between 24 and 48 hours after it affects your heart or lungs.

Quick treatment in a hospital gives you the best chance for a complete recovery.

Can I prevent hantavirus infections?

The best way to prevent hantavirus infections is to protect yourself if you’re in a space where mice or rats could have been. To clean areas with rodent droppings or where rodents could've been:

• Wear rubber gloves and a respirator mask.
• Don’t sweep, vacuum or disturb areas that could have contaminated dust or rodent poop in them.
• Spray the area with disinfectant or bleach solution. Get it very wet and let it sit for at least five minutes.
• Wipe up poop and pee with paper towels and throw them away.
• Clean the area a second time with disinfectant and paper towels.
• When finished, wash your hands with soap and water before and after taking your gloves off.