Hantavirus: For health professionals
On this page
- Key information
- Transmission
- Signs and symptoms
- Diagnosis
- Management and treatment
- Prevention
- Surveillance
Key information
Hantaviruses are a group of zoonotic RNA viruses found in rodent reservoir hosts (such as mice, rats and other rodents) worldwide, including in Canada.
Hantaviruses can manifest as 2 distinct forms of severe diseases:
- hantavirus pulmonary syndrome
- hemorrhagic fever with renal syndrome
The form of disease is dependent on the infecting hantavirus species.
Infection with a hantavirus mainly occurs by directly inhaling aerosolized particles from the droppings, urine or saliva of infected rodents.
Person-to-person transmission of hantaviruses is uncommon. Limited person-to-person transmission has only been reported with the Andes species of hantavirus, usually following prolonged close contact. The Andes virus is endemic to South America, mainly in Argentina and Chile.
Hantavirus infections are rare, and the risk of getting a hantavirus infection in Canada or in other parts of the world is low.
There is no specific treatment for hantavirus infections. Patient management focuses on symptomatic support, which may include aggressive hemodynamic and respiratory support.
Hantavirus pulmonary syndrome is a nationally notifiable disease in Canada.
Health professionals in Canada should be vigilant. It's vital to recognize, report and promptly investigate symptoms of hantavirus infection.
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Transmission
Hantaviruses are found around the world and are spread by infected rodents, such as mice and rats, most often through their droppings, urine and saliva.
Hantavirus can be transmitted when people:
- inhale aerosolized virus particles from rodent secretions, such as feces, urine or saliva while cleaning enclosed or poorly ventilated spaces
- touch objects or eat food contaminated with the feces, urine or saliva from infected rodents
- direct contact with the waste or body fluids of infected rodents, including through bites (rare)
The Andes virus is the only species of hantavirus with evidence of person-to-person transmission. The majority of reported Andes virus infections result from zoonotic exposure, though a few recognized outbreaks have occurred with a limited chain of person-to-person transmission. These events are typically associated with close and prolonged contact with symptomatic individuals. However, current evidence does not rule out the possibility of transmission through casual contact. This suggests that the virus may be highly transmissible during the early and relatively short period of the total illness.
Signs and symptoms
The incubation period ranges from 1 to 6 weeks, with most cases becoming symptomatic 2 to 4 weeks after exposure.
The 2 main types of diseases caused by hantaviruses are:
- hantavirus pulmonary syndrome (North and South America)
- hemorrhagic fever with renal syndrome (mainly in Europe and Asia)
Hantavirus pulmonary syndrome
Hantavirus pulmonary syndrome is a severe disease with a high case fatality rate ranging from 30% to 50%.
Multiple hantavirus species have been identified that cause hantavirus pulmonary syndrome. Sin Nombre virus is the only species that causes hantavirus pulmonary syndrome that is endemic to Canada. The Andes virus is responsible for most cases in South America.
Hantavirus pulmonary syndrome has 3 clinical phases.
1. Prodrome (or febrile)
The prodrome phase typically lasts 2 to 8 days and is characterized by non-specific symptoms, such as:
- fever
- chills
- myalgia
Other symptoms include:
- nausea
- vomiting
- abdominal pain
- dizziness
- headache
2. Cardiopulmonary phase
The second phase begins with the rapid onset of progressive cardiopulmonary symptoms, characterized by:
- a dry cough and dyspnea
- non-cardiogenic pulmonary edema
- hypotension
- respiratory failure
- cardiogenic shock
- arrythmias
- coagulopathy
Oliguria may also occur during this phase.
This phase lasts from 2 to over 7 days depending on the severity of the infection. However, it may resolve over a shorter period of time, characterized by the rapid clearance of pulmonary edema and resolution of fever and shock.
When fatal, the majority of deaths occur within 24 hours of the onset of the cardiopulmonary phase.
3. Convalescence
Convalescence may be prolonged and full recovery may take weeks to months. Commonly reported symptoms include:
- fatigue
- myalgia
- shortness of breath
- slow recovery of motor skills
Hemorrhagic fever with renal syndrome
There are multiple hantavirus species that can cause hemorrhagic fever with renal syndrome. These include Seoul virus, Hantaan virus and Puumala virus. The clinical course and severity of hemorrhagic fever with renal syndrome can vary significantly depending on the infecting hantavirus species. Case fatality rate ranges from less than 1% to 10%.
Typical presentation includes:
- fever
- hemorrhage
- hypotension
- acute kidney injury
In severe infections, patients generally progress through 5 clinical phases.
1. Febrile phase
The febrile phase may begin abruptly with symptoms such as:
- high fever
- headache
- back ache
- nausea
- vomiting
- abdominal pain
Additional symptoms that may occur in multiple phases include:
- petechiae
- facial flushing
- erythematous rash
2. Hypotensive phase
The hypotensive phase is characterized by the sudden onset of hypotension, which may progress to shock and hemorrhagic manifestations.
3. Oliguric phase
During the oliguric phase:
- urinary output falls quickly
- blood pressure may return to normal or become high
- severe hemorrhage may occur
The risk of fatal outcome is highest in the oliguric phase.
4. Diuretic phase
Patients who survive the acute phases of illness enter into a diuretic phase 10 to 14 days after onset of symptoms, indicating the beginning of recovery.
5. Convalescent phase
Recovery from acute infection is rapid, but full recovery may take weeks to months.
Diagnosis
Laboratory testing
Hantavirus pulmonary syndrome and hemorrhagic fever with renal syndrome are diagnosed by laboratory testing.
Of the following diagnostic markers, 1 or more must be positive:
- presence of hantavirus RNA by RT-PCR (reverse transcription polymerase chain reaction)
- presence of hantavirus-specific IgM (immunoglobulin M) or four-fold rise of IgG (immunoglobulin G) titres
- positive immunohistochemistry for hantavirus antigen
The National Microbiology Laboratory (NML):
- performs reference testing for International Health Regulations reporting
- analyzes genomic sequence of provincial or territorial samples for hantavirus in Canada
- has established molecular testing for hantavirus within some provincial laboratories
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Management and treatment
Treatment of hantavirus infections is generally supportive. Early recognition of disease is critical.
Potential antiviral treatment options are under investigation. However, there are currently no established routine treatments. Only consider antiviral treatment after consulting with an infectious diseases physician.
Hantavirus pulmonary syndrome
Infection can progress rapidly from the prodromal to the cardiopulmonary phase. As such, patients may need care in a tertiary centre with extracorporeal membrane oxygenation (ECMO) capability.
Recognizing infection early improves likelihood of survival, with intensive care unit monitoring and pulmonary and hemodynamic support.
Hemorrhagic fever with renal syndrome
Patients who need supportive care for hemorrhagic fever with renal syndrome may need dialysis and admission to an intensive care unit.
Avoid nonsteroidal anti-inflammatory drugs to reduce the risk of more severe acute kidney injury.
Preclinical trials indicate that treatment with intravenous ribavirin may help improve outcomes if used very early in the disease. However, given the serious side effects of this drug, only initiate this therapy after considering the pros and cons.
Prevention
There is no approved vaccine or antiviral medication to prevent hantavirus infection in Canada. Only consider antiviral post-exposure prophylaxis after consulting with an infectious diseases physician. Ribavirin has demonstrated inconsistent benefit in randomized trials for hantavirus pulmonary syndrome and is associated with hematologic toxicity.
Favipiravir is another antiviral that has been used for post-exposure prophylaxis in high-risk contacts of Andes hantavirus infection or prodromal treatment. However, there is no clinical efficacy evidence in established hantavirus pulmonary syndrome.
Routine practices are enough to manage infection prevention and control for patients with a suspected or confirmed hantavirus infection. The only exception is if the infection is caused by the Andes virus. In these cases, put additional precautions in place informed by the interim recommendations for infection prevention and control of Andes hantavirus in healthcare settings.
Learn more:
- Hantavirus: Spread, prevention and risk
- Respiratory infectious diseases: Reduce your risk
- Andes virus: Infectious substances pathogen safety data sheet
- Sin Nombre virus: Infectious substances pathogen safety data sheet
- Hantaan orthohantavirus: Infectious substances pathogen safety data sheet
- Management of contacts of Andes virus cases from the MV Hondius cruise ship (World Health Organization)
- Interim guidance: Public health management of contacts of Andes virus cases from MV Hondius cruise ship (May 26, 2026)
Surveillance
Hantavirus pulmonary syndrome is a nationally notifiable disease. Nationally notifiable diseases are infectious diseases that have been identified as surveillance and control priorities by the federal, provincial and territorial governments.
The Canadian Notifiable Disease Surveillance System (CNDSS) receives reports of hantavirus pulmonary syndrome cases from provincial and territorial public health authorities. Only confirmed cases are reportable to CNDSS.
Provinces and territories have their own legislation for reporting priority infectious diseases. Consult the provincial or territorial public health authority for reporting requirements in your jurisdiction.
Since testing began in the early 1990s and as of May 1, 2026, 168 cases of hantavirus infection have been identified in Canada.
On May 17, 2026, Andes virus infection was confirmed in 1 repatriated Canadian passenger who had previously been aboard the MV Hondius cruise ship, the site of an Andes hantavirus outbreak.
About 200 cases of hantavirus pulmonary syndrome occur each year worldwide, mainly in North and South America.
Between 150,000 and 200,000 cases of hemorrhagic fever with renal syndrome due to a hantavirus infection occur each year worldwide. Most of these occur in China, where the average case fatality rate is from 1% to 10%.
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