Last updated: 4/8/2025
Years published: 1994, 1995, 1998, 2000, 2009, 2012, 2016, 2025
NORD gratefully acknowledges Emily Pannuzio, Arya Park, Caroline Zorn, and Ella Gaul, NORD Editorial Interns from the University of Notre Dame and Gregory Mertz, MD, Emeritus Professor of Internal Medicine, University of New Mexico, for assistance in the preparation of this report.
Hantavirus pulmonary syndrome (HPS) is a rare infectious disease caused by hantaviruses, primarily the Sin Nombre hantavirus (SNV) in most of the United States.1
The average age of onset for HPS is 38, although individuals of all ages may encounter and develop the disease.2
Transmission most often occurs through direct or indirect (airborne) contact with the saliva or waste products of infected rodents that carry the virus, most commonly deer mice.2 Rural populations, in addition to those who work in construction, janitorial, agricultural and pest control jobs, have increased risk for HPS as they have high potential exposure to wild rodents.3
Initial symptoms commonly present three to four weeks (range 1-8 weeks post-hantavirus exposure, and may include fevers, muscle aches (myalgias) and headaches.4 Around 3-6 days after this initial phase, the disease may progress rapidly to respiratory distress characterized by cough, shortness of breath, low blood pressure (hypotension), shock, fluid in the lungs (pulmonary edema) and respiratory failure.5,6
HPS caused by SNV is rare and there are only around 30 affected individuals per year.1 The disease is very severe and has a very poor prognosis. There are currently no specific treatments to combat HPS, but supportive care methods targeting the severity of symptoms may help improve the outcome for affected people. For example, oxygen therapy may be used to treat respiratory compromise, while hypotension can be managed with medications similar to dopamine and norepinephrine.7 In severely affected individuals, extracorporeal membrane oxygenation (ECMO) may be used as a life-saving measure.6
HPS primarily affects adults with the mean age of onset being 38 years.2 Common initial symptoms of HPS are non-specific and include fever, muscle aches, fatigue and headache.4 These are likely followed by shortness of breath, rapid breathing (tachypnea) and rapid heart rate (tachycardia).4 Additional symptoms such as chills, abdominal pain, dizziness, diarrhea, malaise joint pain (arthralgia), back or chest pain and sweating may also be present.4
Hantavirus primarily affects the lungs and kidneys which contributes to respiratory distress, hypotension and shock as the disease advances to the “cardiopulmonary phase”.6 Coughing and shortness of breath may occur 4-10 days after initial disease onset, which is characteristic of the more severe cardiopulmonary phase of HPS. Additionally, excess fluid (edema) may accumulate in the lungs leading to low oxygen levels in the blood (hypoxemia).5,8 HPS, once progressed into the cardiopulmonary phase, carries a 40% mortality rate overall.9 One-third of affected people die within the first 48 hours of hospital admission.9
HPS is caused by viruses of the family Hantaviridae and the genus Orthohantavirus.9 In viruses, a family is a broad group of viruses sharing similar characteristics, while a genus is a smaller, more specific group within a family. HPS in the U.S. is primarily caused by the “Sin Nombre hantavirus (SNV)”, a virus within the Orthohantavirus genus and carried primarily by the deer mice (Peromyscus maniculatus).10,11 The deer mouse is found throughout most of the U.S. except the southeast, with most SNV infections occurring west of the Mississippi river.11
Not all deer mice carry the virus, but those that do not have symptoms.11 People are infected through indirect or direct contact with an infected rodent’s saliva, feces, urine, or by inhalation of viral-containing aerosol particles.12 Other hantaviruses known to cause human disease in the U.S. include the New York virus, transmitted by the eastern white-footed mouse, Black Creek Canal virus from the cotton rat in Florida and Bayou virus from the rice field mouse in Texas and Louisiana.11
Additionally, several other hantaviruses have been found in other rodent species in the U.S., though these strains have not yet been detected in humans. In South America, the Andes virus causes severe HPS in Argentina and Chile.2 Additionally, Andes virus can spread through human-to-human contact instead of just rodent-to-human transmission.13
HPS caused by SNV is very rare. There were only 850 people identified in the United States between 1993 and 2021 and an average of around 30 affected individuals per year.1 In North America, HPS affects males slightly more than females with a little over 60% of reports involving males.1,2 In the United States, around 74-78% of affected individuals are Caucasian, while around 17-20% of the documented reports involving American Indian Alaskan Native populations.1,2 Children are affected less frequently, yet experience a briefer timeframe between symptom onset and death.14 Fewer diagnoses in children may be related to misdiagnosis rather than actual disease incidence.14 Geographic exposure to rodent droppings appears to be the primary risk factor, as many reports were initially concentrated in the southwestern U.S.15 Rural populations, in addition to those who work in construction, janitorial, agricultural and pest control jobs, have increased risk due to potential exposure to wild rodents.3,16
Hantavirus pulmonary syndrome (HPS) can be difficult to detect early because its symptoms are similar to other respiratory infections like the flu or Q fever. To diagnose HPS, doctors look at symptoms, history of rodent exposure and specific lab tests. These tests can show blood changes like low platelets (thrombocytopenia) and unusual white blood cells such as atypical lymphocytes.5
Early symptoms of HPS include sudden high fever (over 101°F), chills and stomach issues.18 However, as commented above, since these symptoms are not unique, lab tests are needed to confirm the presence of Hantavirus.18,19,20
The Centers for Disease Control and Prevention (CDC) defines an HPS diagnosis based on: 18,19
The CDC mentions the use of different tests to detect the virus:21
There are currently no specific antiviral drugs or vaccines for HPS, so treatment focuses on managing symptoms. Because HPS affects multiple organs, affected people need to be seen by many different specialists that should work together as a team in a coordinated way. Among others, the team of specialists should include experts in infectious disease, pulmonology, hematology, intensive care and neurology.9
Since fluid can quickly build up in the lungs, careful monitoring of fluids, electrolytes and blood pressure is critical. 22 In severe cases, patients may need oxygen therapy or mechanical ventilation. 9 A treatment called extracorporeal membrane oxygenation (ECMO) can help in life-threatening cases with a 70% success rate when used early.6
Preventive measures include avoiding areas where deer mice leave droppings such as storage sheds, basements and wood piles.18 People cleaning such areas should wear a fit-tested N95 face mask and rubber gloves and sanitize the area with bleach solution to prevent contact with infectious dust.23 People having symptoms such as fever, muscle or back pain and headache one to eight weeks after exposure to mouse droppings should seek immediate medical attention, as HPS can progress rapidly within hours.2,11
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Toll-free: (800) 411-1222
TTY: (866) 411-1010
Email: [email protected]
Some current clinical trials also are posted on the following page on the NORD website: https://rarediseases.org/for-patients-and-families/information-resources/info-clinical-trials-and-research-studies/
For information about clinical trials sponsored by private sources, in the main, contact: www.centerwatch.com
For more information about clinical trials conducted in Europe, contact:
https://www.clinicaltrialsregister.eu/
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Learn more https://rarediseases.org/patient-assistance-programs/caregiver-respite/The information provided on this page is for informational purposes only. The National Organization for Rare Disorders (NORD) does not endorse the information presented. The content has been gathered in partnership with the MONDO Disease Ontology. Please consult with a healthcare professional for medical advice and treatment.
The Genetic and Rare Diseases Information Center (GARD) has information and resources for patients, caregivers, and families that may be helpful before and after diagnosis of this condition. GARD is a program of the National Center for Advancing Translational Sciences (NCATS), part of the National Institutes of Health (NIH).
View reportOrphanet has a summary about this condition that may include information on the diagnosis, care, and treatment as well as other resources. Some of the information and resources are available in languages other than English. The summary may include medical terms, so we encourage you to share and discuss this information with your doctor. Orphanet is the French National Institute for Health and Medical Research and the Health Programme of the European Union.
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