Hantaviruses are zoonotic viruses that naturally infect rodents and are occasionally transmitted to humans. Infection in people can result in severe illness and often death, although the diseases vary by type of virus and geographical location. These viruses cause hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS).
The two main types of diseases caused by a hantavirus are:
Hemorrhagic fever with renal syndrome can be a mild, moderate or severe disease, depending upon which hantavirus you are infected with. The clinical course can be divided into 5 phases:
The prodrome phase begins with:
These symptoms are followed by:
This phase typically lasts 3 to 7 days.
The low blood pressure stage (hypotensive phase) can last from a few hours to several days. During this stage, blood pressure suddenly drops and may lead to shock or serious bleeding problems.
The oliguric phase typically lasts 3 to 7 days. During this time, blood pressure may return to normal or become high, and urinary output falls quickly. Severe haemorrhage may occur. Spontaneous diuresis indicates the beginning of recovery.
Hantavirus pulmonary syndrome has 4 clinical phases:
The prodrome phase typically lasts 3 to 6 days and is characterized by fever, myalgia and malaise. Other symptoms include:
This is followed by the rapidly progressive cardiopulmonary phase, which is characterized by:
Hypotension and oliguria may also occur during this phase.
The diuresis phase involves rapid clearance of pulmonary edema and resolution of fever and shock.
Hantaviruses are carried by rodents. The virus is found in excreta (urine, feces, saliva) of infected rodents. The primary mode of transmission to humans is through the inhalation of the aerosolized virus from feces (droppings), urine or saliva of infected rodents.
PHO’s Public Health Guidance for Hantavirus (Andes Virus) provides public health guidance for the identification, assessment and management of suspect, probable and confirmed ANDV cases, and their contacts.
For patients with an epidemiological link and compatible symptoms; airborne, contact and droplet precautions should be implemented.
For detailed IPAC recommendations see Public Health Ontario's May 8, 2026 At A Glance: Infection Prevention and Control Precautions for Hantavirus, Andes Strain.
Health professionals should consult the Public Health Ontario (PHO) Microbiologist for testing information and guidance.
There is no specific treatment for Hantavirus infection. Hospitalization may be needed for serious illness. Treatment is limited to supportive care, including rest and hydration. May also include oxygen therapy to help with severe respiratory distress.
There is no preventative vaccine against Hantavirus currently available.
All suspected and confirmed cases of Hantavirus infection must be reported to TPH by calling 416-392-7411 during regular business hours (8:30 a.m. to 4:30 p.m., Monday to Friday) or 311 outside these hours.