Hantavirus

WHAT IS HANTAVIRUS INFECTION?

Hantavirus infection is a rare but serious illness. Typical symptoms are flu-like and include fever, headache, nausea, vomiting, muscle aches, diarrhea, abdominal pain and shortness of breath. These symptoms can occur any time between three days to six weeks (usually occurring around 14 days) after exposure. Infection without symptoms is rare. 

HOW IS HANTAVIRUS INFECTION SPREAD?

The usual host of this virus is the deer mouse, although other rodent species have been shown to be infected. The deer mouse can be pale gray to reddish brown, and has white fur on its belly, feet and underside of the tail. It is found widely throughout the United States and Canada.

The deer mouse lives primarily in rural and semi-rural areas, but can also reside in urban centers. Although deer mouse numbers may vary with habitat and location, a recent survey in southern Manitoba found that deer mice were the dominant species representing over 95% of the mice caught.

The virus spreads to people when they:

• breathe air contaminated by deer mouse saliva, urine or feces containing infectious hantaviruses; or
• accidentally rub eyes, mouth or broken skin with hantavirus-infected deer mouse saliva, urine or feces.

In theory, transmission might also occur by:

• eating food contaminated by infected deer mouse saliva, urine or feces; or
• being bitten by an infected deer mouse.

TREATMENT:

There is currently no cure for this virus. However, early detection and medical care is extremely important. This is because 30 to 40% of hantavirus cases result in death, usually within a few days after the initial symptoms appear. Those who are infected with the virus may be given medication for fever and pain, as well as oxygen therapy.

WHAT SAFETY MEASURES CAN BE TAKEN?

Specific risk factors that have been associated with contracting hantavirus in Canada include sweeping or vacuuming areas contaminated with deer mice feces, urine or rodent nests, working with/around abandoned vehicles, handling firewood, etc.

Recommended precautionary measures include:

• sealing points of entry into buildings, such as cracks in the foundation or holes.  Mice can squeeze through cracks as thin as a dime;
• discourage rodents from living in buildings by using rodent-proof storage containers for food, pet and garbage storage;  
• clean up spilled/dropped food in eating areas;
• keeping grass short and yards clean;
• securing garbage with tight-fitting lids; 
• using snap-traps or poison to catch mice;
• handle dead rodents (or nests) while wearing nitrile or rubber gloves;
• clean all traps, wash nitrile or rubber gloves with a disinfectant before taking them off and wash hands with soap and water after handling carcasses or traps.

Please refer to the divisional safe work procedure for cleaning up after rodents.