Rats are among the most significant disease-carrying pests in the world. They transmit illness directly through bites, urine, and droppings — and indirectly through the fleas, ticks, and mites they carry. In the United States, rats are associated with Salmonella, leptospirosis, rat-bite fever, and hantavirus, among others.

Diseases Rats Transmit Directly to Humans

Direct transmission occurs through contact with rats, their urine, droppings, or nesting material — or through rat bites and scratches.

Hantavirus Pulmonary Syndrome

Hantavirus is transmitted primarily through airborne particles from rodent urine, droppings, and nesting material. When dried material is disturbed — sweeping, vacuuming, or even walking through an infested area — the virus becomes airborne and can be inhaled. Hantavirus pulmonary syndrome is rare but has a high fatality rate (approximately 38%). The deer mouse is the primary carrier in the U.S., though Norway rats can carry other hantavirus strains. This is a critical reason to never dry-sweep or vacuum rodent droppings without proper protective equipment.

Leptospirosis

Leptospirosis is caused by bacteria shed in rat urine. Humans become infected through contact with contaminated water or soil — entering through cuts in skin, mucous membranes, or by swallowing. Flooding events increase exposure risk significantly. Symptoms range from mild flu-like illness to serious complications including kidney and liver failure (Weil’s disease). Leptospirosis is more common than most people realize; cases are often misdiagnosed as flu or meningitis.

Rat-Bite Fever

Caused by Streptobacillus moniliformis bacteria, rat-bite fever is transmitted through bites or scratches, or through contact with rat urine or droppings. Symptoms typically include fever, rash, and joint pain, appearing 3–10 days after exposure. Untreated, it can cause serious complications including endocarditis. Children and people with weakened immune systems are at greatest risk.

Salmonellosis

Rats contaminate food and food preparation surfaces with Salmonella bacteria through their droppings and urine. This is a major concern anywhere rodents have access to kitchens, food storage areas, or food processing facilities. Salmonellosis causes diarrhea, fever, and abdominal cramps — symptoms most people attribute to other causes, often without ever suspecting rodents.

Lymphocytic Choriomeningitis (LCMV)

Spread through contact with house mouse and rat urine, droppings, or nesting material. LCMV causes neurological disease and is particularly dangerous for pregnant women — infection during pregnancy can lead to birth defects or fetal loss.

Diseases Rats Spread Indirectly (Through Fleas, Mites, and Ticks)

Rats serve as hosts for ectoparasites that carry their own diseases:

  • Plague — historically devastating, still present in the western U.S. The bacteria (Yersinia pestis) is transmitted by fleas that feed on infected rodents
  • Murine typhus — transmitted by rat fleas, causes fever, headache, and rash. Endemic in parts of the southern U.S. and increasingly reported in suburban areas
  • Rickettsialpox — transmitted by rat mites; causes a chicken-pox-like rash

How Rats Contaminate Your Home

Understanding contamination pathways helps explain why rat infestations are a genuine health emergency, not just a nuisance:

  • A single rat produces approximately 50 droppings per day and continually leaks urine as it travels
  • Rats travel the same routes repeatedly, depositing pathogens along walls, floors, and any surface they contact
  • Rats nest in insulation, inside walls, and under appliances, contaminating areas that are difficult to clean without professional remediation
  • Rats chew through food packaging, directly contaminating food stores

When to Call a Professional

If you have evidence of a rat infestation — droppings, gnaw marks, burrows, tracks, or visual sightings — treat it as the health issue it is and call a professional promptly. Don’t attempt to clean up rodent-contaminated areas without consulting guidelines on proper protective equipment (N95 mask minimum, gloves, ventilate the area before cleaning).

Rodent control requires addressing the full population, not just setting a few traps. Entry points must be identified and sealed to prevent reinfestation. DIY efforts typically result in partial population reduction while the remaining population continues to reproduce and contaminate.

What Miller Pest Solutions Does About Rodents

Miller Pest Solutions takes rodent control seriously — because the health stakes are real. We serve homeowners and businesses in Des Moines, Kansas City, and Omaha with professional rodent elimination programs that address the problem completely, not just partially.

As a family-owned company operating since 2001, QualityPro Certified and NPMA members, our technicians understand the rodent species common to the Midwest, their behavior patterns, and the most effective strategies for elimination and exclusion. We identify how rodents are entering your structure, eliminate the existing population, and work with you on preventing reinfestation.

Learn more at our rodent control page.

Get a Free Phone Bid

Don’t let a rat infestation become a health crisis. Call Miller Pest Solutions today for a free phone bid. Des Moines: (816) 420-0340, Kansas City: (816) 409-3884, Omaha: (402) 532-8863. Or request a quote online.