If you’ve been hearing more about hantavirus lately, you’re not imagining it. Rodent activity across Ontario has surged in 2025 and 2026, and with more mice turning up in attics, garages, and crawl spaces across the Greater Toronto Area, homeowners have questions—and understandably so.

At GreenLeaf Pest Control, our phones have been busy with calls about hantavirus risk, safe cleanup of mouse droppings, and what to do when you suspect a rodent problem. This guide covers everything Ontario homeowners need to know: what hantavirus is, what symptoms look like, how it spreads, and how to protect your home and family.

What Is Hantavirus?

Hantavirus is a virus transmitted primarily by wild rodents, most commonly the deer mouse (Peromyscus maniculatus). In humans, exposure to the virus can lead to Hantavirus Pulmonary Syndrome (HPS), a serious and potentially life-threatening respiratory illness.

The disease progresses in two phases. The early stage closely resembles the flu. If it advances, it can cause severe respiratory distress as the lungs fill with fluid—which is why early awareness matters.

Is Hantavirus Common in Ontario?

The short answer: confirmed cases in Ontario are extremely rare. According to Public Health Ontario, the vast majority of Canadian hantavirus cases occur in Western Canada—British Columbia, Alberta, and Saskatchewan—where deer mouse populations are larger and more widespread.

That said, deer mice do exist in Ontario, particularly in rural, cottage country, and semi-rural suburban areas. As urban sprawl and construction continue to push rodent populations into residential neighbourhoods, the overlap between humans and potentially infected mice is growing. The risk remains low—but it is not zero, and proper precautions during any rodent cleanup are non-negotiable.

Hantavirus Symptoms: What to Watch For

This is the question our team hears most. If you’ve recently cleaned up mouse droppings or disturbed an old nest, here’s what to watch for.

Early Symptoms (1–5 Weeks After Exposure)

The incubation period for hantavirus is typically one to five weeks. Early symptoms are flu-like and include:

• Fever and chills
• Fatigue and muscle aches (especially in the thighs, hips, and back)
• Headaches
• Nausea, vomiting, or stomach pain (in some cases)

Late-Stage Symptoms (4–6 Days After Early Onset)

If the infection progresses to Hantavirus Pulmonary Syndrome, symptoms escalate quickly and can include:

• Shortness of breath
• Coughing, often producing fluid from the lungs
• Extreme fatigue
• Low blood pressure

Important: HPS can deteriorate rapidly. If you have been in contact with rodent droppings or nesting materials and develop any of these symptoms, seek medical attention immediately and inform your doctor about the potential exposure. This content is informational only—always consult a medical professional.

How Is Hantavirus Spread?

Hantavirus is not contagious between people. Humans become infected by inhaling microscopic airborne particles (aerosols) contaminated with infected rodent urine, saliva, or droppings. This most commonly happens when those materials are disturbed.

High-Risk Activities

• Sweeping or vacuuming dry mouse droppings—this kicks contaminated particles into the air
• Disturbing old nests in attics, garages, crawl spaces, or sheds
• Opening seasonal cottages or storage areas after a long winter
• Handling nesting materials without proper protective equipment

Why Rodent Activity Is Surging Across Ontario in 2026

Hantavirus may be associated with rural settings, but the rodent pressures driving risk are increasingly urban and suburban. GreenLeaf has seen a significant spike in service calls across the GTA and surrounding areas, and several factors are driving it:

• Rapid construction and development displaces established rodent populations, pushing them into nearby residential neighbourhoods
• Aging infrastructure—foundations, rooflines, and utility entries in older homes provide easy access points for mice and rats
• Complex rooflines common in high-income communities like Oakville and Mississauga create hard-to-detect nesting cavities
• Milder winters mean less die-off in rodent populations between seasons

Our teams handling Vaughan pest control, Barrie rodent removal, and Brampton pest control have all reported above-average call volumes for rodent entry and attic contamination this season. The same pattern holds in Newmarket, Aurora, Bradford, and Ajax. If you’ve seen signs of mice—droppings, gnaw marks, scratching in walls—don’t wait to act.

How to Safely Clean Up Mouse Droppings

Never dry-sweep or vacuum mouse droppings. This is the single most important rule. Dry disturbance aerosolizes contaminated particles and dramatically increases your inhalation risk. Follow the protocol recommended by Canadian public health authorities:

• Ventilate first: Open windows and doors and let the area air out for at least 30 minutes before entering
• Wet it down: Spray droppings and surrounding surfaces with a bleach-based disinfectant (1 part bleach to 9 parts water) until thoroughly soaked. Wait 5 minutes before wiping
• Use proper PPE: Wear rubber or latex gloves, and a properly fitted N95 respirator at minimum
• Wipe, don’t sweep: Use disposable paper towels or rags to collect the wet material
• Double-bag and dispose: Seal waste in plastic bags and dispose of in an outdoor garbage bin
• Wash up: Remove gloves carefully, then wash hands thoroughly with soap and water

If the contamination is extensive—covering large areas of insulation, flooring, or HVAC components—stop and call a professional. DIY cleanup of a serious infestation is not worth the risk.

Professional Rodent Remediation: What GreenLeaf Provides

When a rodent problem goes beyond a trap and a wipe-down, professional intervention is the safest and most effective route. Our residential pest control services across the GTA cover the full scope of rodent management:

• Complete Rodent Exclusion: Our technicians identify and permanently seal every exterior entry point—gaps in foundations, roofline penetrations, utility entries, and vents. No poison-only approach; we stop the source.
• Attic Restoration: We remove contaminated insulation, disinfect the space using hospital-grade biohazard protocols, and restore your attic to a safe, healthy state.
• Hantavirus Disinfection: For properties where significant rodent activity has occurred, we provide professional rodent cleanup services designed to eliminate biohazard risks and restore your home’s air quality safely.
• Home Protection Plan: Our ongoing monitoring program detects and deters rodent activity year-round, before mice get inside. The best cleanup is the one you never need.

Frequently Asked Questions

Is hantavirus a risk in Ontario?

Confirmed hantavirus cases in Ontario are extremely rare. Most Canadian cases occur in western provinces. However, deer mice—the primary carrier—do exist in Ontario, and as rodent populations increase in urban and suburban areas, taking proper precautions during any rodent cleanup is important.

How long after exposure do hantavirus symptoms appear?

The incubation period is typically one to five weeks, though it can range from one to eight weeks. Early symptoms resemble the flu—fever, fatigue, and muscle aches. If you were recently exposed to rodent droppings and develop these symptoms, contact a physician immediately and mention the potential exposure.

Can I clean up mouse droppings myself?

For small, contained areas with minor evidence of mice, careful DIY cleanup following public health protocols (ventilate, wet disinfectant, N95 mask, gloves, no sweeping) is possible. For extensive contamination—especially in attics or with compromised insulation—professional remediation is strongly recommended.

How do mice get into my attic?

Common entry points include gaps around roofline soffits and fascia, utility penetrations (pipes, cables, HVAC), deteriorating vent covers, and foundation cracks. A mouse can squeeze through a hole the size of a dime. Professional exclusion identifies and seals all of these points, not just the obvious ones.

Does GreenLeaf serve my area?

Yes. GreenLeaf Pest Control serves homeowners across the GTA and surrounding communities, including Toronto, Mississauga, Oakville, Vaughan, Brampton, Newmarket, Aurora, Bradford, Ajax, Barrie, and more. Contact us to confirm service in your specific area.

Protect Your Home Before the Problem Gets Bigger

The risk of hantavirus in Ontario may be low, but the damage mice cause to your home’s insulation, wiring, and air quality is a near-certain outcome of an untreated infestation. Rodents don’t wait, and neither should you.

If you’ve spotted droppings, heard scratching in your walls, or suspect mice have moved into your attic or garage, contact GreenLeaf Pest Control today for a thorough inspection and eco-friendly, effective remediation. Our team serves homeowners across the GTA and surrounding areas—we’re the call you make before a small problem becomes an expensive one.