Man has been plagued by bed bugs (Cimex lectularius) for thousands of years.They are found all over the world.
By the twentieth century some UK cities had bed bug infestations in as many as one third of all homes. In the 1950s, DDT and other pesticides were introduced that helped combat the rampant infestation. These were extremely effective and for a while it seemed that bed bugs had become a thing of the past. However, in the 1970s it was discovered that DDT and other pesticides were very harmful to humans, and their use was outlawed. Since then they have been in resurgence.
Over the past decade, there has been a marked increase in bed bug infestation throughout the world. Many factors have contributed to this growth, but the unstoppable growth in world travel is perhaps the most significant.
In their adult state bedbugs are around 6 – 7 mm in length – about the same size and shape as an apple pip. Prior to feeding, they are very thin and can hide in cracks not much thicker than a piece of paper. They can engorge themselves with human blood in less than 15 minutes causing their bodies to fill to as much as three times its usual size.
Newly hatched bed bugs will require five significant blood meals to reach adult size. In between blood meals they moult by shedding their exoskeleton. They take around 5 or 6 weeks to reach maturity. Once mature they will begin the process of laying new eggs. Bed bugs can lay between one and five eggs per day with an incubation period of around 10 days in warm conditions. A typical female will lay up to 500 eggs in her lifetime.
Bed bugs most often feed at night time (not exclusively) when people are asleep. When they feed, they inject a salivary secretion into the wound to prevent coagulation. The fluid can cause a person’s skin to itch and even become swollen. Scratching can cause sores which often become infected.
Bed bugs are masters of concealment, seeking refuge in cracks and crevices. But unlike many other pests which often inhabit very similar harbourages from one location to the next, bed bugs can be found in a very wide variety of places. This is one reson they are perhaps the most diificult indoor pest to get rid of. Common harbourages include: joints in bed frames, headboards, beneath loose wallpaper, under floorboards, desks, entertainment centres, nightstands, behind base moulding in wall-mounted artwork, etc.
Bedbugs have the ability to enter diapause – a state of dormancy lasting up to a year or even more – if their food source is removed. This is why it is vital to continue sleeping in the bed in an infested room after any chemical treatment. The presence of a human in the bed will encourage surviving bedbugs to come out and into contact with pesticides. If a human is absent, the bedbugs will either try to find a new source of food by leaving the room or will enter diapause.