Hantavirus infection is a serious viral disease that can cause severe illness affecting the lungs or kidneys. The infection is found worldwide and is mainly spread to people through contact with rodents or their droppings, urine, or saliva. Hantavirus infection can lead to life-threatening problems, but early recognition and supportive care can improve outcomes. Preventing rodent exposure is the most effective way to reduce the risk of hantavirus infection.

Hantavirus infection is a disease caused by a group of viruses called hantaviruses, which are found in rodents around the world. These viruses can cause two main types of illness in people:

• Hantavirus pulmonary syndrome (HPS), which mainly affects the lungs, is most common in the Americas. It causes lung problems such as fluid buildup and trouble breathing.
• Hemorrhagic fever with renal syndrome (HFRS), which mainly affects the kidneys, is more common in Europe and Asia and can lead to kidney failure and bleeding problems. Some types of hantavirus, such as the Seoul virus, are found worldwide and can cause HFRS.

The infection often starts with flu-like symptoms but can quickly become much more serious. Both syndromes can be severe and sometimes deadly.

Hantavirus infection spreads mainly from rodents to people through contact with rodent urine, droppings, or saliva. The virus can get into the air when rodent waste is disturbed, and people can become infected by breathing in this contaminated air. Less commonly, the virus can enter the body through broken skin, the eyes, nose, or mouth after touching contaminated materials.

People can also get hantavirus infection by being bitten or scratched by an infected rodent, or by eating food contaminated with rodent body fluids. Most hantaviruses do not spread from person to person. However, the Andes virus, found in South America, can sometimes spread between people who have close contact. The risk of infection increases in places where rodents live or where their droppings or urine may be present, such as homes, barns, or campsites. The incubation period for developing hantavirus infection is typically around two weeks or so after exposure, but can be as long as six to seven weeks.

The main risk factors for hantavirus infection involve contact with rodents or their droppings. People are more likely to get infected if they:

• Live or work in areas where rodents are common, such as rural homes, farms, or cabins
• Clean up rodent nests, droppings, or urine, especially in closed spaces with poor ventilation
• Handle rodents as pets or in laboratories, especially without protective equipment
• Work in jobs that involve exposure to rodents, such as pest control, animal care, or forestry
• Store food in ways that attract rodents or leave food uncovered
• Camp, hike, or sleep outdoors in areas with rodent infestations
• Have pet rats, especially in homes with young children, pregnant women, or people with weakened immune systems

Symptoms of hantavirus infection usually begin suddenly and can range from mild to very severe. Early symptoms often resemble those of the flu, but the illness can quickly become life-threatening. The symptoms depend on whether the infection causes HPS or HFRS.

Common early symptoms include:

• Sudden fever, often with chills
• Muscle aches, especially in the large muscles of the back, hips, and thighs
• Headache, which can be severe
• Nausea, vomiting, or diarrhea
• Abdominal pain or back pain, which may be intense

Symptoms of HPS can include:

• Cough and shortness of breath, which can become severe within hours
• Chest tightness or difficulty breathing, as fluid builds up in the lungs
• Low blood pressure, which can lead to shock
• Rapid heartbeat or dizziness

Symptoms of HFRS can include:

• Flushed face or redness of the eyes
• Low blood pressure
• Rash or small spots of bleeding under the skin
• Low urine output or no urine, which means the kidneys are not working well
• Blood in the urine or stool, or easy bruising
• Swelling, especially in the legs or around the eyes

People should contact a health care provider promptly if they have sudden fever, muscle aches, or trouble breathing after possible rodent exposure, or if they develop confusion, severe bleeding, or signs of kidney failure.

Diagnosis of hantavirus infection is based on symptoms, possible rodent exposure, and laboratory tests. A doctor will ask about recent activities, travel, and any contact with rodents or their droppings. During a physical exam, the doctor will check for fever, breathing problems, low blood pressure, and signs of kidney or bleeding issues.

Medical tests used to diagnose hantavirus infection include:

• Blood tests to detect hantavirus antibodies, which show if the body is fighting the virus
• Polymerase chain reaction (PCR) tests, which look for the virus’s genetic material in blood or tissue samples
• Complete blood count, to check for low platelets (thrombocytopenia) and other blood changes
• Kidney function tests, to measure how well the kidneys are working
• Liver function tests, to check if the liver is affected by the infection
• Urinalysis, to look for blood or protein in the urine
• Chest X-ray, to look for fluid in the lungs in people with breathing problems
• Echocardiography (ultrasound of the heart), to rule out heart causes of lung fluid

Treatment for hantavirus infection focuses on supportive care, as there is no cure for the virus. The main goal is to manage symptoms and prevent complications. The type of care depends on whether the infection causes HPS or HFRS.

Main treatments include:

• Hospital care with close monitoring; severe cases may require care in an intensive care unit (ICU)
• Oxygen therapy or mechanical ventilation, to help with breathing if the lungs are affected
• Careful fluid and blood pressure management, to prevent shock and organ failure
• Dialysis, which is a machine that cleans the blood, for people with kidney failure from HFRS
• Intravenous ribavirin, an antiviral medicine, may be used early in HFRS to reduce severity and risk of death
• Medications to control fever, pain, and other symptoms
• Treatment of secondary infections, if they occur
• Extracorporeal membrane oxygenation (ECMO), may be used in the most severe cases of HPS. In ECMO, a machine temporarily supports breathing by moving blood out of the body, adding oxygen, and returning it to the body.

Early intensive care can improve survival, especially for people with severe breathing or kidney problems.

Complications of hantavirus infection can be serious and affect many organs. The risk and type of complications depend on several factors, including the form of the disease and how quickly treatment is started.

Possible complications include:

• Respiratory failure, which means the lungs cannot provide enough oxygen to meet the body’s needs
• Shock, a dangerous drop in blood pressure that can damage organs
• Kidney failure, which may require dialysis to remove waste from the blood
• Bleeding problems, such as easy bruising, blood in urine or stool, or internal bleeding
• Fluid overload, which can cause swelling and breathing problems
• Heart problems, such as abnormal rhythms or heart failure
• Multiorgan failure, where several organs stop working
• Death, which can occur in severe cases, especially without early treatment

Hantavirus infection can be prevented by avoiding contact with rodents and their droppings. The most effective prevention strategies focus on keeping rodents out of homes and workplaces and cleaning up safely.

Prevention steps include:

• Sealing holes and gaps in homes, garages, and sheds to keep rodents out
• Storing food in rodent-proof containers and cleaning up spilled food right away
• Using traps to reduce rodent populations around living areas
• Cleaning up rodent droppings, urine, or nests with gloves and disinfectant, and avoiding sweeping or vacuuming, which can stir up the virus
• Ventilating closed spaces before cleaning to reduce airborne virus
• Wearing protective gear, such as masks and gloves, when cleaning areas with rodent activity
• Keeping wild rodents away from pet rodents and testing new pet rats for hantavirus before bringing them home
• Avoiding pet rodents in homes with young children, pregnant women, or people with weakened immune systems

The outlook for people with hantavirus infection depends on the type of syndrome, the virus strain, and how quickly treatment begins. HPS can be very severe, with about 30% to 50% of people with lung symptoms dying from the disease, especially if not treated early. Those who survive the first few days of severe illness often recover fully within two to three weeks.

HFRS has a wide range of outcomes. Mild cases may recover completely, while severe cases can lead to death in up to 15% of people, depending on the virus type and other health problems. Most people who survive HFRS recover kidney function within weeks to months, though full recovery may take up to six months in some cases.

“While hantavirus infections can be severe and life threatening, human infections are still very rare,” says Albert Shaw, MD, PhD, a Yale Medicine infectious disease specialist. “Previous outbreaks in the United States were all associated with rodent exposure and nearly all cases occurred west of the Mississippi River. Only one case of HPS has ever been reported in Connecticut. It occurred in 2014 and was linked to rodent exposure in Vermont.”

The best way to prevent hantavirus infection and other infectious diseases is to limit rodent exposure, Dr. Shaw adds.

This fact sheet was medically reviewed in June 2026.