Loyola University Chicago

Healthy Homes & Healthy Communities

Rodents & Insects

Rats and Mice

Where are they found?

Rats can live in walls, trees, vines, and holes in the ground. (Green and HH)

What causes them?

Rodents enter homes through holes inside and outside the home. Mice can squeeze through a hole the size of a nickel, and rats can squeeze through a hole the size of a half dollar. (CDC)

How does it affect health?

Mice do not have bladder control; therefore they leave a stream of urine as they search your house for food. (Green and HH)

  • Many people are allergic to mouse urine.
  • Exposure to mouse urine can cause asthma attacks in some people.

Many people are allergic to mouse dander, which can also lead to asthma attacks. (GHH)

Rats have been known to attack sleeping children and babies. (Green and HH)

Worldwide, rats and mice spread over 35 diseases. These diseases can be spread directly through contact with rodent feces, urine, saliva, or rodent bites. Rodent diseases can also be spread indirectly through ticks, mites, or fleas that have fed on infected rodents.(CDC)

  • Diseases spread by direct contact in the US: Hantavirus pulmonary syndrome, Leptospirosis, Lymphocytic Chorio-meningistis (LCM), plague, rat-bite fever, salmonellosis, Tularemia. (CDC)
  • Diseases spread by indirect contact in the US: Babesiosis, Colorado tick fever, Cutaneous Leishnamiasis, Human Granulocytic Anaplasmosis, Lyme disease, Murine typhus, Scrub typhus, Rickettsialpox. (CDC)

What local (city and state policies are in place to regulate and/or prevent this toxin?

Chicago housing code (NCHH)

  • 7-28-150 Spreading of vermin poison.
    • It shall be unlawful for any person to spread, or to cause or permit any agent or employee to spread, any poison for the purpose of killing rats, mice, insects, or other vermin, in any public way or public place in the city; and it shall be unlawful for any person to spread or to cause or permit any agent or employee to spread, any poison for such purpose in any yards, court, passageway, or other open place on private premises, or on the outside of any building or structure, or in any place within a building which is open to the general public, or where pet dogs, cats, or other domestic animals or fowls have access, without placing the same in a receptacle of such kind or character that it can be reached only by the kind of vermin which the poison is intended to kill, or without placing a wire or other guard about same in such way that no child, or domestic animal, domestic fowl, or other harmless creature can reach the same.
  • 7-28-660 Rat-stoppage.
    • Every building, structure, or parcel on which a building has been demolished or is being constructed within the city shall be rat-stopped, freed of rats and maintained in a rat-stopped and rat-free condition.
  • 7-28-690 Unlawful to remove rat-stoppage.
    • It shall be unlawful for the owner, occupant, contractor, public utility company, plumber, or any other person, to remove the rat-stoppage from any building or structure for any purpose and fail to restore the same in satisfactory condition, or to make any new openings that are not closed or sealed against the entrance of rats.
  • 7-28-700 Structural changes.
    • Whenever conditions inside or under any building or structure provide such extensive harborage for rats that the building commissioner deems it necessary to eliminate such harborage he may require the owner or occupant in charge of any such building or structure to install suitable cement floors in basements, or to require such owner or occupant to correct such rat harborage as may be necessary in order to facilitate the eradication of rats.

What interventions are effective?

Seal holes and cracks using wire mesh; reduce food and water availability; conduct regular cleaning to reduce pest urine and feces; use appropriate traps. (GHH)



What are they?

Cockroaches are insects that can live a month without food, but only one week without water. (GHH)

Some roaches will lay 37 eggs at a time. (GHH)

Where are they found?

Cockroaches are likely to be hiding in spaces that are tiny, tight, dark, cluttered, and near food and water. (GHH)

Kitchens and bathrooms typically have the highest number of cockroaches due to the presence of food products and moisture from plumbing fixtures. (NCHH)

Apartment buildings often have the worst infestations as a coordinated effort by the landlord and all tenants is required to eliminate cockroaches. (NCHH)

What causes them?

Any home can have cockroaches. Lack of general maintenance and cleaning allow cockroaches to proliferate by providing them food, water, and shelter. Cracks and holes in housing provide paths for cockroaches to enter the inside. (NCHH)

How does it affect health?

Cockroach frass or waste is dangerous for your family as it can trigger asthma attacks when breathed in. (GHH)

Cockroach frass causes gastrointestinal and respiratory illness. (NCHH)

What local (city and state policies are in place to regulate and/or prevent this toxin?

Most housing codes put responsibility for cockroach control on the landlord if two or more units are infested. (NCHH)

What interventions are effective?

Reduce food and water availability; practice proper food storage and disposal; Do not leave dirty dishes in the sink overnight; clean crumbs, grease, etc. (GHH)


Dust Mites

What are they?

Dust mites are microscopic spider-like creatures with eight legs. Dust mites eat dead skin cells and need food, moisture and warmth for survival. (Green and HH)

Unlike other insects, mites are not capable of ingesting water; in order to obtain water they must absorb it from the air. (NCHH)

Mites take about one month to develop from an egg into an adult and have an adult life span of about 2–4 months. A single adult female may lay up to 100 eggs. (NCHH)

Where are they found?

Dust mites live in dust, fabric, bedding, furniture, and carpets. (GHH)

Ideal temperatures for dust mites are between 68–77 degrees Fahrenheit. Dust mites thrive in locations where dead skin cells are most likely to be found. (NCHH)

What causes them?

Dust that is carried in from outside the home on shoes and clothing. (NCHH)

How do they affect health?

Dust mites’ feces are breathed in and can trigger asthma attacks. People who are allergic to them can develop rashes from too much exposure. (Green and HH)

What interventions are effective?

Use allergen blocking mattress and pillow covers; wash bed linens weekly in hot water; regularly wash, freeze, or put in dryer pillows and stuffed animals. (GHH)

Use a HEPA filter vacuum on all carpeted areas and on furniture and upholstery. (GHH)

Keep humidity levels down by using a dehumidifier, ventilation fan, or air conditioning. (GHH)


Bed Bugs

What are they?

“Bed bugs (Cimex lectularius)are small, flat, parasitic insects that feed solely on the blood of people and animals while they sleep.” (CDC)

  • Red-brown in color, wingless, and range in size from 1–7mm. (CDC)
  • They can survive for several months without a blood meal. (CDC)

Where are they found?

They are found around the globe and can be found anywhere from developing countries to 5-star hotels. The cleanliness of living conditions does not determine where bed bugs can be found. (CDC)

Infestations usually occur near places where people sleep, such as “apartments, shelters, rooming houses, hotels, cruise ships, buses, trains, and dorm rooms.” (CDC)

They hide during the day in mattress seams, box springs, bed frames, headboards, dresser tables, inside cracks or crevices, behind wallpaper, or any clutter or objects around a bed. (CDC)

“Bed bugs have been shown to be able to travel over 100 feet in a night but tend to live within 8 feet of where people sleep.” (CDC)

The signs of a bed bug infestation include:

  • Bed bugs’ exoskeletons after molting.
  • Bed bugs in the fold of mattresses and sheets.
  • Rusty-colored blood spots due to their blood-filled fecal material that they excrete on the mattress or nearby furniture.
  • A sweet musty odor. (CDC)

What causes them?

Bed bugs are usually transported from place to place as people travel. (CDC)

  • They travel in the seams and folds of luggage, overnight bags, folded clothes, bedding, furniture, and anywhere else where they can hide. (CDC)

How does they affect health?

“Bed bugs should not be considered as a medical or public health hazard. Bed bugs are not known to spread disease.” (CDC)

They are an annoyance because they may cause itching and loss of sleep. Excessive itching can sometimes increase the chance of a secondary skin infection. (CDC)

Bed bug bite responses vary from person to person; some people show no physical signs of a bite and others may have a more serious allergic reaction to bed bug bites. (CDC)

What local (city and state) policies are in place to regulate and/or prevent this toxin?

Illinois Railroad Sanitation Act: 610 ILCS 85/1 to 85/4. Requires railcars that will be occupied by the public to be free from bedbugs. Requires regular cleaning and inspection of railcars. Provides for penalties. (NCSL)

On June 5, 2013 the Chicago City Council passed an ordinance aimed at stopping the spread of bed bugs. (MTO)

  • Landlord responsibilities:
    • Supply a new tenant with an informational brochure about the spread of bed bugs.
    • Provide pest control services when bed bugs are found by a pest management professional as many times as necessary to eliminate the problem.
    • Send a written notice to the tenant explaining their responsibilities before the inspection.
    • Maintain a written record of bed bug control efforts.
    • Inspect and treat if necessary the two units on either side as well as the two units above and below the infested unit.
  • Tenant responsibilities:
    • Notify the landlord in writing of any suspected or known infestation in the tenants’ unit, clothing, furniture, or personal property.
    • Notify the landlord in writing of any recurring or unexplained bites, stings, or sores suspected to be caused by bed bugs.
    • Cooperate with the landlord in the control, treatment, and eradication of bed bugs including:
      • Grant access at reasonable times upon reasonable notice for inspections and treatments/to not interfere.
      • Prepare unit prior to treatment including cleaning, dusting, vacuuming.
      • Properly dispose of personal property that cannot be treated or cleaned before the pest control services.
  • Chicago Bed Bug Ordinance also mandates the disposal of bedding, clothing, furnishing, or other infested material.
    • You may not place, discard, or dispose of any bedding, clothing or furnishing infested on the public way (i.e. dumpsters, sidewalks, hallways). To get rid of infested items, you must enclose them in a plastic bag and label them as infested. (MTO)
  • If any person is found violating the ordinance, that person may be fined $300.00 to $1,000 per day for each offense. (MTO)
  • This ordinance goes into effect October 2013. (MTO)

What interventions are effective?

Laundering fabrics (sheets, drapes, etc) will rid them of bed bugs as long as they are kept away from the infested area. (NCHH)

Mattress and Box Spring Encasements will trap bed bugs that are already on the mattress and prevent them from feeding, thus killing them. (NCHH)

Bed bug infestations are commonly treated by insecticide spraying. The best way to prevent bed bugs is regular inspection for the signs of an infestation. (CDC)