Animals > Animal Diseases > Hantavirus Pulmonary Syndrome  

Hantavirus Pulmonary Syndrome

What is hantavirus?

Hantavirus is a viral disease of wild mice that can be spread to humans through direct or indirect contact. In Canada, deer mice (Peromyscus maniculatus )are the principal carriers of hantavirus. Deer mice are pale grey with white fur on their underbellies. They live mainly in rural and semi-rural wooded areas. In humans, the virus causes a severe cardiopulmonary illness resulting in death in approximately 45 per cent of cases.

What are the signs of the disease in mice?

Mice do not show signs of illness and will appear healthy.

How is the disease transmitted to people?

Mice shed hantavirus in fresh urine, droppings, and saliva. Their nesting materials can become contaminated and so can the air when these materials are disturbed. In areas of heavy contamination, humans can inhale the virus which leads to hantavirus pulmonary syndrome. Less frequently, humans become infected by ingesting contaminated food or water and, in rare cases, by being bitten by an infected mouse.

How serious is hantavirus to the Canadian public?

Although the risk of being infected with the virus is low, the mortality rate in humans with hantavirus pulmonary syndrome is high. Canada’s first human case was reported in 1994 in British Columbia. Since then 45 cases have been reported in Western Canada and 16 of those resulted in death. Workers in agricultural or rural settings (e.g.farmers, grain handlers) are at the highest risk. Incidental contact may put telephone installers, plumbers, electricians, pest control officers, construction and wildlife workers, and hikers and campers at risk.

What are the symptoms in humans?

Clinical signs of infection may develop in humans from one to five weeks after exposure to infected rodents and their droppings. Early signs are fever, muscle pain, and fatigue. Some may also experience headaches, dizziness, vomiting, or diarrhea. Late symptoms, which include coughing and shortness of breath, appear four to 10 days after the initial phase. The lungs fill with fluid, which can quickly lead to an inability to breathe and in severe cases, death from suffocation .

Is there a treatment or vaccine against hantavirus?

There is no current vaccine or treatment for this disease. Research is on-going to develop a vaccine that could protect people with a higher risk of infection. Patient care is administered through careful fluid intake and mechanical ventilation (use of a respirator).

What precautions should be taken?

Avoid contact with wild rodents and their droppings. Remember that wild rodents may also carry other infectious diseases.

Indoors and Outdoors

• Place woodpiles or any stacks of lumber, bricks, stones, etc. at least three metres from dwellings.

• Dispose of garbage in containers with tight-fitting lids.

• Keep food and water (including pet food) covered and store in rodent-proof containers.

• Keep items (e.g. clothes, boxes) off the floor to discourage rodent nesting.

• Correct any conditions that support the growth of mould, mildew, or other fungi in the home.

• Mow grass closely and cut or remove brush and dense shrubbery to a distance of at least three metres from the home. Trim overhanging limbs of any trees or shrubs.

• Place traps baited with peanut butter in areas where rodents may enter.

• Always wear rubber or plastic gloves when handling dead rodents or rodent-contaminated materials. Place and seal in a plastic bag and then place the bag in a sealed garbage can. Rodent remains or materials can also be buried.

Campers and hikers

• Typical tourist activities provide limited or no risk of exposure to rodents or their excretions.

• Do not use cabins or other enclosed shelters that are potentially rodent infested until they have been appropriately cleaned and disinfected.

• Do not pitch tents or place sleeping bags near rodent droppings or possible rodent shelters (e.g. garbage dump, woodpiles).

• Use a ground cover or a tent with a floor.

Can hantavirus be transmitted from person to person?

No. Hantavirus is not contagious. There is relatively no risk of transmitting the disease from one person to another.

Can pets become infected?

No. Hantavirus does not affect any other animal species; however, domestic animals may bring infected rodents into contact with humans. Domestic mice kept as pets are not at risk. NEVER keep a wild rodent as a pet.

How to get more information?

Contact your Canadian Food Inspection Agency Area Office:

You can find your local Canadian Food Inspection Agency District Office on the CFIA Web site or by consulting the blue pages of your local phone directory.

P0313E-03
August 2003