Health Impacts
Reducing Exposure
More Information


Health Impacts

Exposure to rodents can trigger asthma attacks. Studies have shown a linkage between rodent allergy and asthma symptoms. Exposure to rodents (mice and rats) has been linked to increased asthma symptoms among laboratory workers who handle rodents and are sensitized to them. Other studies have established links between rodent allergies and asthmatic symptoms in lab workers. Research published in 2004 found similar linkages in residential settings. Rodent allergens are likely from rodent urine, saliva, or skin.

It is clear that many inner-city residents are exposed to and allergic to rodents. A major study on asthma among inner-city children found that nearly 20 percent of asthmatic children had been sensitized to rats and 15 percent were sensitized to mice. This is important to note, as research has found mouse allergen in 82 percent of U.S. homes.

Rodents can also expose humans to diseases such as hantavirus. Exposure to such disease vectors is rare but can cause severe health problems.


Reducing Exposure

Integrated pest management (IPM) approaches offer effective means of eliminating rodents from the home. IPM methods focus on preventing infestations, trapping rodents, and limited use of lower-toxicity pesticides. However, even after a rodent population is controlled, rodent hair, urine, and fecal allergens may remain and can trigger allergic reactions in some people.

Designing, maintaining, and renovating buildings to minimize rodents is an effective prevention-based approach.

  • Seal holes and cracks in building foundations, utility openings, and joints between materials. Use corrosion-proof materials such as copper or stainless steel mesh. Rodents can chew through many other materials and squeeze through tiny openings.
  • Add rodent barriers to foundation walls to make it more difficult for them to enter a building. For example, heavy-duty wire mesh along the outside of a foundation is an effective barrier.
  • Seal passages through interior floors, walls, ceilings, and kick spaces. If possible, keep kick spaces open to limit places rodents can hide. (Kick spaces are the gaps between the bottom of cabinetry or built-in furniture and the floor.)
  • Keep bushes and trees at least three feet from homes. Bushes and trees near a home provide food, a living place, and sheltered passage for rats and rodents.
  • Ensure trash is stored in secure containers (covered garbage cans and dumpsters).
  • Store food in rodent-proof containers.

More Information

Beyond Pesticides

Building Science Corporation

Cohn R, Arbes S, Yin M, Jaramillo R and Zeldin D. Journal of Allergy and Clinical Immunology, National prevalence and exposure risk for mouse allergen in US households, June 2004.

Gumm, Brian, Home Energy, “Integrated Pest Management in the Home,” Vol. 21 Iss. 6 pp. 36-39 (Nov-Dec 2004)

Kattan M, Mitchell H, Eggleston P, Gergen P, Crain E, Redline S, et al. Pediatr. Pulmonol, Characteristics of Inner-City Children with Asthma: The National Cooperative Inner-City Asthma Study, 24:253-262, 1997

National Academy of Science, Institute of Medicine – Clearing the Air: Asthma and Indoor Air Exposures 2000.

Pesticide Action Network

U.S. Centers for Disease Control and Prevention