The bed bug (Cimex lectularius) has been a pest of humans for thousands of years but after the 1940’s and the introduction of DDT the numbers significantly decreased for a period of time. The improvement in hygiene in many countries also contributed to the decline of the insect. However the numbers and presence of bed bugs has increased significantly in recent years due to the increase in global travel and tourism.
Although the adult and immature stages are blood suckers, bed bugs have not been linked with diseases of man. The developing nymphs and adults have piercing and sucking mouth parts often causing severe irritation as a result of the bites. Infections are more common in hotels, motels and buildings where sleeping facilities exist.
Adult bed bugs are 4-5mm long. Oval shaped bodies. Rusty brown in colour. Prior to feeding their bodies are flat and after a blood meal they turn a reddish colour and are distended and oval in shape.
Once the young hatch they moult about five times through immature nymphal stages before reaching adulthood. A blood meal between each moult is essential to their continued development. The life cycle from egg to adult can be as short as 50 days or as long as 12 months dependent on availability of hosts.
Males, females and the immature stages are all blood suckers and usually obtain their hosts blood a few hours before dawn. They then return to their hiding places in cracks and crevices in furniture near beds and in part of mattresses. Skin that has been discarded from developing nymphs and fine excreta are often found on sheets and when the infestation is heavy a bug-like odour may be present.
Before laying eggs the female must have a blood meal. During egg laying, she glues the eggs to surfaces near where she resides. Each female will lay over 200 eggs in her lifetime being 12 months.
The bed bug usually injects an anticoagulant that can cause severe irritation in many victims. These are usually scratched which can lead to infection of wounds, but the bed bug does not usually convey diseases when it pierces the skin.
Bed bugs can be carried from sites of infestation in luggage, on clothing and in furniture. It is this way that infestations occur in hotels and motels.