07/06/2026
OVERVIEW
Hantavirus pulmonary syndrome is a rare infectious disease that begins with flu-like symptoms and progresses rapidly to more severe disease. It can lead to life-threatening lung and heart problems. The disease is also called hantavirus cardiopulmonary syndrome.
Several strains of the hantavirus can cause hantavirus pulmonary syndrome. They are carried by different types of rodents. The most common carrier in North America is the deer mouse. Infection is usually caused by inhaling hantaviruses that have become airborne from rodent urine, droppings or saliva.
Because treatment options are limited, the best protection against hantavirus pulmonary syndrome is to avoid contact with rodents and safely clean up rodent habitats.
SYMPTOMS
The time from infection with the hantavirus to the start of illness is usually about 2 to 3 weeks. Hantavirus pulmonary syndrome advances through two distinct stages. In the first stage, which can last for several days, the most common signs and symptoms are:
* Fever and chills
* Muscle aches or pain
* Headache
Some people also experience:
* Nausea
* Stomach pain
* Vomiting
* Diarrhea
As the disease progresses, it can lead to damaged lung tissues, fluid build-up in the lungs, and serious problems with lung and heart function. Signs and symptoms may include:
* Cough
* Difficulty breathing
* Low blood pressure
* Irregular heart rate
When to see a doctor
The signs and symptoms of hantavirus pulmonary syndrome can worsen suddenly and may quickly become life-threatening. If you have flu-like symptoms that progressively worsen over a few days, see your health care provider. Get immediate medical care if you have trouble breathing.
CAUSES
Rodent carriers
Hantavirus pulmonary syndrome is a human disease found only in North and South America. Each strain of the hantavirus has a preferred rodent carrier.
The deer mouse is the most common carrier of the virus in North America and Central America. In the United States, most of the infections occur in the states west of the Mississippi River.
Other carriers in North America include the rice rat and cotton rat in the Southeast and the white-footed mouse in the Northeast. Rodent carriers in South America include the rice rat and the vesper mouse.
TRANSMISSION
The virus is present in the rodent's urine, f***s or saliva. You can come in contact with the virus in the following ways:
* Inhaling viruses — the most likely form of transmission — when they become airborne from disturbed rodent droppings or nesting materials
* Eating food contaminated with mouse saliva, urine or droppings
* Touching things contaminated with the virus, such as a nest, and then touching your mouth, eyes or nose
* Being bitten or scratched by an infected rodent
Person-to-person transmission of the virus has only been recorded with a strain of the virus found in South America called the Andes virus.
EFFECT OF THE VIRUS
When hantaviruses reach the lungs, they invade tiny blood vessels called capillaries, eventually causing them to leak. Your lungs fill with fluid (pulmonary edema), resulting in severe dysfunction of the lungs and heart.
RELATED DISEASE
Another disease caused by different strains of the hantavirus is called hemorrhagic fever with renal syndrome, which causes severe kidney disease. These variants of the virus have other animal carriers in Africa, Asia and Europe.
RISK FACTORS
In the United States, hantavirus pulmonary syndrome is most common in rural areas of the West. However, any exposure to rodent habitats can increase the risk of disease.
Common sites for exposure to rodent nests, urine and droppings include:
* Farm buildings
* Infrequently used buildings, such as storage sheds
* Campers or seasonal cabins
* Camp sites or hiking shelters
* Attics or basements
* Construction sites
Activities that can increase the risk of exposure to the hantavirus include:
* Opening and cleaning long unused buildings
* Cleaning up rodent nests or droppings without appropriate precautions
* Working in a field that increases exposure to rodents, such as construction, utility work, pest control and farming
COMPLICATIONS
Hantavirus pulmonary syndrome can quickly become life-threatening. Severe disease can result in failure of the heart to deliver oxygen to the body. Each strain of the virus differs in severity. The death rate due to the strain carried by deer mice ranges from 30% to 50%.
~ Mayo Clinic
