Hantavirus is a virus primarily carried by rodents. It typically spreads to humans who inhale airborne particles from mice and rat droppings, urine, and saliva.
Infections in humans are uncommon — and serious. People can become very ill and die from hantavirus complications.
No approved vaccine or specific drug exists to treat hantavirus infection, but patients can survive and fully recover if medical professionals diagnose the sickness early and deliver prompt supportive care.
Hantavirus is making international headlines because of a surprise outbreak on a cruise ship in the Atlantic off the coast of Africa. Three passengers died of suspected hantavirus infection and at least three more passengers appear to be sick with the disease, the World Health Organization announced on May 4, 2026.
“This hantavirus outbreak on a cruise ship is the first reported event of its kind, so it’s worth paying attention to and watching for any similar cases,” says Robert H. Hopkins, MD, medical director of the National Foundation for Infectious Diseases. “A single outbreak like this, however, doesn’t necessarily mean more outbreaks are likely.”
People usually get hantavirus in rural communities on land, not at sea, adds Peter Chin-Hong, MD, an infectious disease specialist and professor of medicine at the University of California San Francisco School of Medicine. “So this is highly unusual,” he says.
A more typical hantavirus incident occurred in 2025 when
Betsy Arakawa, the wife of actor Gene Hackman and a classical pianist, died after exposure to the virus at the couple’s home in New Mexico. A report from the state’s department of public health indicated that the property had eight outbuildings with signs of rodent infestation.
Hantavirus disease in humans is rare.
From 1993 (when public health officials began hantavirus surveillance) to the end of 2023, a total of 890 cases were reported in the United States, with the vast majority in the West and Southwest, according to the Centers for Disease Control and Prevention (CDC).
More than one-third of those infections were fatal.
Symptoms of hantavirus infection in humans may vary depending on which species of virus is involved. (There are at least 24 species known to cause disease in humans.)
In general, hantavirus infections result in one of two symptom clusters (syndromes): HPS (hantavirus pulmonary syndrome) and HFRS (hemorrhagic fever and renal syndrome).
HPS Hantavirus Symptoms
HPS is most likely to occur in the Western Hemisphere. It is considered to be deadlier than HFRS and mostly attacks the lungs.
Signs usually start to show one to eight weeks after contact with a virus source, according to the CDC.
Early symptoms can include:
- Fatigue
- Fever
- Muscle aches, especially in the large muscle groups like the thighs, hips, back, and sometimes shoulders
About half of all HPS patients also experience:
- Headaches
- Dizziness
- Chills
- Abdominal problems, like nausea, vomiting, diarrhea, and abdominal pain
Later signs that appear 4 to 10 days after early symptoms include:
- Coughing
- Shortness of breath
- Tightness in chest as lungs fill with fluid
HFRS Symptoms
HFRS is more likely to occur in Europe and Asia. It mostly affects the kidneys.
Usually signs develop within one to two weeks (or, rarely, up to eight weeks) after exposure to the virus.
Initial symptoms begin suddenly and include:
- Intense headaches
- Back and abdominal pain
- Fever or chills
- Nausea
- Blurred vision
- Possible flushing of the face, inflammation or redness of the eyes, or a rash
Later signs include:
- Low blood pressure
- Lack of blood flow (which causes acute shock as it deprives cells of oxygen and nutrients)
- Internal bleeding (vascular leakage)
- Acute kidney failure, which can cause severe fluid overload
For the most part, hantavirus spreads to humans who inhale airborne viral particles from mice and rat droppings, urine, and saliva.
Typically, hantavirus cases appear in drier environments, such as the Western and Southwestern United States, particularly where rodent habitats and human populations intersect. In these regions where the atmosphere has less moisture, virus particles can more easily become airborne and infect people.
In April 2026, public health officials confirmed a hantavirus case in Nevada, which often experiences drought conditions.
As of this reporting, the cause of hantavirus on the cruise ship is uncertain. The outbreak may have been caused by a rodent infestation on the vessel or possibly human-to-human transmission, which is considered very rare but more likely to occur in enclosed, poorly ventilated environments.
Dr. Chin-Hong suggests that person-to-person transmission may have played a role in this instance because the cruise ship began its journey in South America where a particular strain of the virus called Andes is present and has been known to spread from human to human.
Cruise ships carry a large number of passengers in relatively close quarters, and ventilation in the interior spaces allow viruses to spread widely through the ship, notes Dr. Hopkins. These vessels have been notorious hotbeds for the spread of other infectious diseases, such as COVID-19 and
norovirus.
Hantavirus infection risk is highest in situations that expose a person to rodent habitats. These sites include:
- Infrequently used buildings, such as storage sheds
- Farm buildings
- Campers or seasonal cabins
- Camp sites or hiking shelters
- Attics or basements
- Construction sites
Hantavirus can be very difficult to diagnose because initial symptoms are similar to many common illnesses such as the flu, according to Chin-Hong.
During a physical exam, a healthcare provider may look for:
- Abnormal lung sounds as a result of inflammation
- Signs of kidney failure
- Low blood pressure
- Low blood oxygen levels
“Clinicians need to be very astute to recognize that hantavirus is a possibility,” Chin-Hong says. “Hantavirus will not grow on a routine blood culture. It is typically diagnosed by antibody testing, which may take some time. PCR testing is faster and more sensitive but these tests are not widely available.”
Note that antibody tests look to see if the immune system is producing antibodies against the virus, while PCR tests look for the presence of the virus' genetic material.
Other possible diagnostic tests include urinalysis, and X-ray or computerized tomography (CT) scan of the chest.
There is no specific drug to remedy a hantavirus infection. But early supportive medical care can typically help a person recover, including medications to relieve symptoms such as fever and, if needed, to treat low blood pressure and low oxygen levels.
Hospitalized patients with hantavirus pulmonary syndrome typically receive oxygen and may need mechanical ventilation (a breathing machine) or extracorporeal membrane oxygenation (ECMO), an advanced form of life support.
Individuals with complications such as hemorrhagic fever and renal syndrome require close monitoring of kidney function and may need dialysis.
To lower the risk of hantavirus infection, it’s important to avoid contact with contaminated dust from rodent excretions when cleaning homes, sheds, or other enclosed areas that have been empty for a long time.
- When opening an unused cabin, shed, or other building, open all the doors and windows, leave the building, and allow 30 minutes to air out.
- Return to the building and spray the surfaces, carpet, and other areas with a disinfectant. Leave the building for another 30 minutes.
- Spray mouse nests and droppings with a 10 percent solution of chlorine bleach or similar disinfectant. Allow it to sit for 30 minutes. Using rubber gloves, discard materials in plastic bags.
- Wash all potentially contaminated hard surfaces with a bleach or disinfectant solution. Vacuum only after the area is thoroughly decontaminated. Consider wearing a mask.
- Seal holes and gaps in structures.
- If you have a heavy infestation of rodents, call a pest control company.
Hantavirus is a serious infection that can worsen quickly without hospitalization and aggressive care.
“ICU treatment is key to survival for many patients, which might also explain the high fatality rate as many people in rural areas may not get to the ICU in time,” says Chin-Hong.
Complications of hantavirus infection include heart and lung failure, as well as kidney failure. More than one-third of infections are fatal, according to U.S. government data.
- Hantavirus infection is rare. It mainly occurs in humans who breathe in airborne virus particles from rodent feces and urine.
- Depending on the viral strain, hantavirus can cause a range of symptoms, from headache, fever, and muscle aches to nausea and blurred vision.
- There is no specific medication or vaccine for hantavirus infection but early diagnosis and supportive care (such as with supplemental oxygen) can help with recovery.
- Hantavirus is difficult to diagnose and has a high fatality rate.
