Bed bugs belong to the insect order Hemiptera, the true bugs, most of which are winged insects adapted to sucking plant sap. One family of this order, Cimicidae, has evolved as wingless, blood-sucking parasites on warm-blooded hosts.

There are 91 species in this family of ectoparasites (parasites that live on the exterior of the host organisms). Most of these species live in the nests of either birds

or bats. But two species have evolved as ectoparasites of humans – the common bed bug, Cimex lectularius, and the tropical bed bug, Cimex hemipterus.

Cimex lectularius is the species most commonly found in homes. Adult bed bugs have oval-shaped bodies with no wings. Prior to feeding, they are about ¼ inch long and flat as paper. After feeding, they turn dark red and become bloated. Eggs are whitish, pear-shaped and about the size of a pinhead. Clusters of 1-5 eggs can be found in cracks and crevices. Bed bugs prefer to feed on human blood, but will also bite mammals and birds. Bed bugs bite at night, and will bite all over a human body, especially around the face, neck, upper torso, arms and hands.

Bed bugs have a one-year life span during which time a female can lay 200-400 eggs depending on food supply and temperature. Eggs hatch in about 10 days. Bed bugs can survive up to six months without feeding. Both male and female bed bugs bite.

The human-host relationship may have evolved when humans still lived in caves and were exposed to cave bats. According to Usinger (1966), the two species of Cimex that feed on humans are related to Old World bat-infesting members of the genus that originated in the Palearctic regions. These species were inadvertently spread by explorers to Africa, Australia, and the New World , and became cosmopolitan urban pest species.

In the early 20^th century, with the introduction of central heating, the common bed bug spread farther north and became a more serious pest in parts of northern Europe than it had previously been. But with the development of synthetic insecticides such as DDT and spray systems during the Second World War, humans finally gained the upper hand. (Usinger, 1966)

Over the past half a century, bed bugs had become a rarity, associated with the most marginal of human living conditions. Unfortunately, to the consternation of urban entomologists and public health officials, bed bugs are once again on the rise. A general global resurgence has been reported in Asia, Europe, North America, and Australia.

The reasons for this phenomenal resurgence are not yet clearly understood. Many factors may be playing a role. Among these factors may be:

• Changes in registered pesticides, use patterns, residual levels, and pesticide resistance;
• Socioeconomic conditions leading to increased levels of homeless people living under conditions in which it is difficult to maintain hygiene;
• A populace that has forgotten how to monitor for and control bed bugs;
• Greater mobility that allows bed bugs to spread more quickly to a wide number of establishments, including hostels, shelters, bus stations, dormitories, prisons, hospitals, and hotels.

In Toronto, reports of bed bugs by pest control companies and pest control officials started to increase in 2001. Homeless people told street nurses that bed bugs were a priority medical issue in 2002. By 2003, at least a dozen shelters, hostels, and other forms of public housing were known to have ongoing problems with bed bugs, despite spraying by pest control companies.

In November 2003, a special meeting was organized by Hostel Services of the Toronto Shelter Housing and Support Division, at which advocates for homeless people, shelter personnel, street nurses, public health officials, a university entomologist, and a professional pest control services manager came together to draw up an action plan.

The rise of bed bugs is a concern for many reasons. First, the nocturnal blood-sucking habits of the bugs induce anxiety, worry, stress, and sleeplessness for those infested. The initial bite, though usually painless, may develop into a welt that remains itchy for weeks. With scratching and subsequent infections, these welts can develop into severe skin conditions. This psychological torment alone should justify public health concern.

When the conditions of shelters are such that homeless people prefer not to use them for fear of bed bugs, and sleep in the streets instead, the societal investment in shelters is undermined.

At the same time, the potential of bed bugs for spreading disease cannot be overlooked. According to Harwood and James (1979), bed bugs fulfill all the conditions of efficient carriers of disease (disease vectors). They can be infected with many disease organisms. Ebeling (1978) reported that the organisms associated with plague, relapsing fever, tularemia and Q fever survive for long periods in bed bugs. Olson (2000) found that bed bugs may play a minor role in the transmission of hepatitis B virus, but not other viruses such as HIV.

Although they have not yet been implicated in the spread of any human epidemics, the medical community should maintain a high level of vigilance, given their disease-carrying potential, the ever-evolving dynamics of disease organisms, and the potential of bed bugs to serve as vectors of blood-born diseases from person to person. However, for practical purposes, bed bugs are officially considered only as medical nuisance pests, not as carriers of disease. (As of 2003 when this report was prepared.)

Finally, bed bugs may be a biological indicator of changing social conditions and might foretell the resurgence of other ectoparasites such as lice and fleas and their associated diseases.

For all of these reasons, the situation merits attentive monitoring. At present, it is not clear to what extent, if at all, such monitoring is currently in place in the Toronto Public Health system.

If the resurgence of bed bugs in shelters and other public facilities is not contained, there is the risk of a continuous and escalating growth in the source populations, leading to larger-scale infestations, which will require more frequent and costly control efforts later.

As the source populations grow, the rate of spread will inevitably increase and bed bugs will start to appear in hotels, apartments, theatres, restaurants, public transit, hospitals and eventually detached single family homes. (As of 2006, this has already occurred and is rapidly increasing.)

Most pest control operators and entomologists who have been consulted on this problem agree that Toronto is still at the low end of a potential exponential population growth curve for bed bugs and that the problem is destined to get much worse in the next several years. (As of 2006, this prediction has come true.)

We want to stress that Toronto is not alone or unique in experiencing a bed bug resurgence. (There is now, as of 2006, an epidemic of bed bugs across North America, Australia, and Europe, not only in shelters, public housing, hostels, hospitals, prisons, and other institutions, but also in 5 star hotels and other upscale urban hospitality establishments.) But as one of the many cities experiencing this problem, it does seem that greater attention to this issue is warranted. (This report was prepared in 2003, and by 2006 there is a growing bed bug problem throughout Toronto.)

The primary objective for our Bed Bug Management Program is to achieve complete eradication and/or control of bedbug infestations, within practical limits, for our customer’s premises. We achieve this goal by utilizing the principles of Integrated Pest Management (IPM), which combines a variety of techniques and products that pose the least risk to human health and the environment.

We advise our customers that they may see some living bed bugs for up to 10 days after each of our treatments. This is normal.

Initially, our program utilizes chemical control and is designed to draw the bed bugs out from their hiding places. As we proceed through an ongoing strategic maintenance program, we use monitors and include various other Integrated Pest Management non-chemical techniques in our program such as adhesive traps, in addition to chemical control methods.

Bed bugs are often carried into a building on objects such as furniture and clothing. Bed bugs can occupy almost any narrow space or crevice, sometimes at a considerable distance from beds. Thus, identifying and eliminating such places is an important part of our control strategy.

Bed bugs can be found in areas such as:

• Seams, creases, tufts, and folds of mattresses and box springs;
• Cracks in the bed frame and head board;
• Under chairs, couches, beds, dust covers;
• Between the cushions of couches and chairs;
• Under area rugs and the edges of carpets;
• Between the folds of curtains;
• In drawers;
• Behind baseboards, and around window and door casings;
• Behind electrical plates and under loose wallpaper, paintings, and posters;
• In cracks in plaster;
• In telephones, radios, and clocks;

Our program also includes comprehensive ongoing Sanitation Assessments and consultation with our customers to provide important preventive techniques and other control information that substantially suppresses bed bug infestations. We also provide instructions on how to prepare for a pest control treatment and how to take control of their own ‘personal space management hygiene’ on a daily basis.

We recommend that our customers utilize some or all of the following guidelines. These control methods and ‘personal space management hygiene’ tips and techniques help prevent and suppress infestations of bed bugs:

• Remove or re-glue peeling wallpaper;
• Caulk, putty, or varnish cracks between baseboards, in wood bed frames, flooring, walls, and mouldings.
• Tighten loose wall switch covers;
• Seal any openings where pipes, wires, or other utilities come into the room (pay special attention to walls that are shared between apartments/suites/rooms.)
• Inspect mattresses and bed frames, particularly the folds, crevices and the underside, and other locations where bed bugs are likely to hide. Vacuuming can remove eggs and bed bugs in all stages of development. Canister vacuums with attachments, particularly the brush or nozzle attachment, should be used to get into baseboards, corners, mattress seams, bed frames, and any areas close to the bed, and crevices in upholstered furniture. The attachments should then be cleaned and the vacuum bag disposed of. It is essential to vacuum daily and empty the vacuum immediately and dispose of the vacuum bag;
• Remove all unnecessary clutter which provides harborage for bed bugs;
• Mattresses and box springs can also be put inside plastic mattress bags or wrapped in plastic film and taped, to exclude bed bugs from access to their favourite hiding places;
• Monitor bed bug activity daily by setting out glue boards or sticky tape (double-sided carpet tape is recommended)
• Place carpet tape on the floor around the bed, and around bed legs to catch the bed bugs;