Bed bugs

Quick facts about bed bugs

  • Bed bugs feed on humans and animals and use their blood to grow and reproduce.
  • Bed bugs do not transmit disease to people.
  • Bed bugs live close to where people sleep, rest or sit for long periods of time.
  • Bed bugs are active at night and generally hide during the day.
  • They feed for 2 to 5 minutes and then move quickly to a hiding spot.
  • Do not try to treat bed bugs yourself. Contact a pest control service for effective removal of bed bugs.

You may not realize that you have been bitten. Bite reactions vary from no reaction to mild red spots to severe rash or hives.

 Brownish adult bed bug without wings
Adult bed bug
side by side images of a bed bug before and after a blood meal
Bed bug before and after a blood meal

The return of the bed bug

Bed bugs (Cimex lectularius) were almost completely removed from North America due to mass treatments with highly toxic insecticides that are no longer in use.

Frequent travel, improved treatment methods that target other insects without affecting bed bugs, and a lack of public awareness has led to a rise in the spread of bed bugs.

Identifying bed bugs

Contact an expert to help identify any suspected bed bug specimens.

The "Let’s Beat the Bed Bug" campaign at the University of Minnesota found that 76 percent of samples submitted for identification are not bed bugs.

  • Adult bed bugs are oval, flattened, brown and wingless insects approximately 1/4" to 3/8" long (5-9 mm). They are similar in appearance to a wood tick. 
  • After the bug has taken a blood meal its color changes from brown to purplish-red and it becomes larger and more cigar-shaped.
  • Young bed bugs resemble the adult in shape but are much smaller, 1/16" (1.6 mm), when they first hatch. They are nearly colorless except after feeding.

Life cycle 

  • After mating, females lay white, oval eggs (1/16" long) into cracks and crevices.

  • An individual bed bug can lay 200 to 250 eggs in her lifetime.
  • The eggs hatch in 6 to 10 days and the newly emerged nymphs seek a blood meal.
  • Immature nymphs molt five times (they shed their outer exoskeleton) before reaching adulthood.
  • There may be three or more generations per year. All ages are found in a reproducing population.
  • Under normal circumstances adult bed bugs will live for about 2 to 4 months.

Bed bugs need to feed at least once before each molt, although they could feed as often as once a day.

Young nymphs can survive without a blood meal for days up to several months. Older nymphs and adults can survive longer without a blood meal up to a year under favorable conditions.

Bed bugs are also found in schools, retail facilities, office buildings, libraries and other public areas.

Signs that you have bed bugs

Look where you sleep 

Bed bugs typically group together in out-of-the-way areas. But some bed bugs will live by themselves, away from the rest of an infestation. The best way to check for an infestation is to look for bed bugs where you sleep or rest.

In bedrooms, look particularly on and around:

  • boxsprings, mattresses, bed frames, tufts, folds and buttons on mattresses 
  • furniture such as desks and chairs
  • behind wallpaper, clocks and pictures
  • cracks in wood floors and under the edge of carpet
    Bed bugs clustered under a bed frame
    Bed bugs on a metal bed frame
    Groups of brown bedbugs under a box spring
    Bed bugs on the underside of a box spring
    Brown bed bugs seen along the seam of a mattress spring
    Bed bugs along a mattress seam
    Bed bugs grouped along the seam of a blue backpack
    Bed bugs on a backpack

    Be careful when you travel

    The greatest chance of finding bed bugs is while you are traveling. It is a good habit to check your room whenever on vacation.

    Check your luggage where you typically set it down when you enter your home and where you store it after travelling.

    While bed bugs are most commonly found in bedrooms, infestations can occur in other rooms including bathrooms, living rooms and laundry rooms.

    Look for spots or smears 

    Bed bugs will sometimes deposit fecal spots (digested blood) while they are feeding. These are seen as dark (dark reddish or brownish) spots or smears found on bed sheets, pillowcases and mattresses, or in nearby areas.

    • Dark blood spots on sheets and bedding may indicate bed bug feeding.
    • In severe infestations, bed bugs may be more noticeable.
    • A combination of bugs, cast skins (empty shells of bugs as they grow from one stage to the next) and fecal spots will be very obvious when closely seen.
    Bed bugs, cast skins, and fecal spots can be seen in an infestation
    Bed bug nest

    Inspect carefully

    These insects are small (1/16" to 1/4") and very flat, so they can move into very tight corners and cracks. They have been found under picture frames between the glass and the frame.

    Bed bugs can be found behind electrical outlets and other wall plates.

    • Inspect all areas closely and, if in doubt, contact a pest control service.
    • If you find a bed bug stop inspection and begin control activity.
    • Bed bugs will move from their hiding places once disturbed. All further inspections should be accompanied by control measures.

    How to avoid bringing bed bugs into your home

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    How to get rid of bed bugs

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     | 

    Jeffrey Hahn, Extension entomologist and Stephen Kells, Extension entomologist

    Reviewed in 2018

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