The two common species in New Zealand are Cimex hemipterus (the Tropical bed bug) and Cimex lectularius, (the Common bed bug). Bed bugs (Cimex spp.) are insects (True bugs, order hemiptera) that are wingless and flattened. Adults are a reddish brown, 5-6mm when unfed to almost 10mm when fully blood engorged.
Side view of adult bed bug showing how flat it is even when partially engorged
Stephen Doggett Dept of Medical Entomology, ICPMR
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Bed bugs and faeces, shed skins, and eggs in fold of pillowtop mattress in heavy infestation
Richard Cooper, Cooper Pest Solutions
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Bed bugs are typically active at night and hide during the daytime. Human dwellings provide ideal habitat (temperature, humidity) as well as a blood source and humans are the preferred host for a blood meal. They don’t tend to live on people like lice do, generally the only real contact is during feeding, which may take five to ten minutes. In the absence of humans, bed bugs will feed on other warm blooded animals including dogs, cats, birds & rodents. But usually they live within 2-3m of where people sleep. However for a feed they can travel up to 30 meters up walls, across ceilings, through air conditioning ducts, along wiring, behind walls & even out one window and into another.
As they are very flat they can squeeze into almost any cavity, including mattress seams, beneath loose flooring, behind loose wallpaper, inside box springs, behind pictures and headboards, upholstered furniture, within electrical appliances and behind light switches.
Bed bugs and eggs packed into a crack in a Hotel bed head board. Richard Cooper, Cooper Pest Solutions.
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Bed bugs around electrical outlets.
Stop bedbugs.com
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Bed bugs do not have nests like ants or bees, but do tend to congregate in habitual hiding places. Characteristically, these areas are marked by dark spotting and staining, which is the dried excrement of the bugs. Also present will be hatched and un-hatched eggs, the tannish shed skins of maturing nymphs, and the bugs themselves. Another possible sign are rusty or reddish smears on bed sheets or mattresses from crushed engorged bed bugs. Although it’s often stated that bed bugs have a telltale “buggy” odor, the smell is seldom evident except in extreme infestations and should not be relied upon for detection.
Eggs are approximately 1mm, cream in colour with a slight bend. They are laid individually in crevices in dark areas, preferably onto textured materials (Fabrics, wood, behind pictures, in furniture, along edges of baseboards, under floor boards etc). They will be cemented firmly onto the surface and not easily removed.
Close up of empty bed bug egg cases on the fabric of a mattress
Stephen Doggett, Department of Medical Entomology ICPMR |
Bed bugs have five larval (nymph) stages. The first instar nymph emerges from the egg approximately 7-10 days after it has been laid. The nymphal stages have a similar body shape to the adults but start out translucent and cream in colour in the first instar, becoming darker in the later instars. The size of the juveniles varies between 1-4mm depending on growth stage. The bed bug moults into each consecutive life stage and requires a blood meal to do so. They can remain dormant for several months without a blood meal but they do not moult without one. Under optimum conditions all five larval stages can be completed in about a month. The ability to survive without a blood meal is longer at cooler temperatures - potentially a year or longer at 12°C or less.
Bed bug nymph feeding on the arm of a human host.
Piotr Naskrecki, CDC
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Adult female bed bug with rounded abdomen.
Stephen Doggett, Dept medical entomology ICPMR |
Under favorable conditions the newly emerged female will feed and mate and then start laying eggs 3-6 days later. In perfect conditions 3-6 eggs are laid a day, more commonly 5-7 per week. Females can last 6 months to 2 years, during which time they may lay 200-500 viable eggs. Both adult male and female bed bugs take repeated blood meals during their lives. Females require blood for the development of eggs.
Diseases
Although bed bugs can harbor various pathogens, transmission to humans has not been proven and is considered unlikely. At least 27 agents of human disease have been found in bed bugs, including viruses, bacteria, protozoa, and parasitic worms. None of these agents reproduce or multiply within bed bugs, and very few survive for any length of time inside a bed bug. There is no evidence that bed bugs are involved in the transmission (Via bite or infected faeces) of any disease agent, including hepatitis B virus ad HIV.
Though not known to carry diseases, bed bugs can substantially reduce quality of life by causing discomfort, sleeplessness, anxiety, and embarrassment. Heavy rates of feeding in children can result in significant blood loss and eventually lead to anaemia, especially in malnourished children. Their medical significance is most commonly attributed to itching and inflammation from their bites. Many people have mild to severe allergic reaction to the bites, in rare cases, anaphylaxis (severe, whole-body reaction). These bites can also lead to secondary infections of the skin such as impetigo, ecthyma, and lymphanigitis.
Bed bug bites on a woman’s arm.
Richard Cooper, Cooper Pest Solutions |
Delayed reaction from bed bug feeding on arm of researcher.
Harold Harlan, DPMIAC, Armed Forces Pest Management Board |
Bed bug Control
Bed bugs are often associated with dirty conditions, but can live in very clean new homes as there are still plenty of harborage sites and hosts for feeds. However in very cluttered homes obviously more habitat is provided. Also when buildings are in a state of deterioration more habitat is provided behind peeling wallpaper, cracks around doors, windows, floorboards etc. Bed bugs can shelter from insecticide by living in piles of toys, clothes etc. They can be transported from place to place on clothing or in suitcases but do not typically venture too far once they have established in a new suitable habitat.
Conventional insect repellents, like those used to deter ticks and mosquitoes, do not appear to be as effective against bed bugs. Therefore, attempting to avoid being bitten by applying insect repellent at bedtime is not recommended. Sleeping with the lights on is also not likely to deter hungry bed bugs, as they will adjust their feeding cycle to the host’s sleeping patterns
The best option for preventing bites is by reducing the likelihood of exposure to bed bugs. This can only be achieved by reduction of potential habitat, and regular inspections. Decluttering is one of the best ways of reducing potential harbourage sites and also makes detection easier. General maintenance (i.e. keeping paint, walls, flooring etc. in good condition to reduce number of potential harbourage sites) can also help. To protect yourself when travelling and to reduce the likelihood of collecting “hitch-hikers”, it is wise to put your luggage on a stand (or other hard surface) while you inspect the room for signs of bed bugs.
One of the biggest obstacles to success in bed bug control is excessive clutter, which provides unlimited areas for bed bugs to hide and to lay eggs (And protect them from pesticides!)
To help guard against bed bugs while traveling, take a moment to inspect beds. A small flashlight is useful for dimly-lit areas. It is advisable to keep luggage on a stand or other hards surface to prevent bugs crawling into your baggage.
Dark spots on mattress and box spring are a telltale sign of bed bugs.
M. Potter, University of Kentucky.
Pest Management techniques may be used to control the infestation, including:
- Reduction of habitat & Disposal of items
- Steam
- Encasement
- Vacating a Room
- Insecticides
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- Heat treatment
- Extreme cold
- Physical removal
- Traps
- Barriers
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The 'Climbup Interceptor' underneath a bed leg. |
The BB Secure Ring on a bed leg. |
Specialised sniffer dogs can be used to detect the sweet smell which infestations produce and traps are available but many are impractical (Large, require electricity or a carbon dioxide bottle, not viable for hotel rooms where guests may be deterred from staying). As yet no traps have been devised which are particularly efficient (some sticky traps placed in heavily infested areas may not catch bed bugs) so are not advised as a control tool at this stage.
Bed bugs spread readily and any live stage that is transported has the potential to start a new infestation elsewhere, thus; No infested items should be removed from the property before they have been thoroughly treated or encased. Otherwise bedbugs can easily be spread throughout the building or to other buildings. Any item removed from the property must be properly disposed of or treated to kill all stages which may be present. Samples should be properly bagged/placed in secure tubes for identification.
Think you have bedbugs? Capture, place in a small container in the freezer overnight and forward to NZBEL for identification. Click
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