Bed Bug Biology
Where did they come from?
Bed bugs have been around for over 3,500 years, originally parasites of bats but gradually became adapted to feeding on human hosts. Although humans are the preferred host, bed bugs feed on many warm-blooded animals. Animal hosts include poultry, rats, mice, dogs, cats, pigeons, canaries, rabbits, and guinea pigs. Mentions of Bed Bug infestations can be found in both Greek and Roman history and so it is clear that the insect has been a pest of man for a long time.
They are now mainly found infesting hotels and boarding houses, particularly in large cities such as London or more recently, Paris. They are most commonly found in bedrooms where they live in cracks and crevices. Feeding is carried out during the night when they emerge from their harbourage points and climb on the sleeping occupant of the room. Their sole food source is blood. Incidents of infestations have shown a slight up-turn in numbers following end of Covid restrictions, as a result of increases in the number of back-packers transporting the insects between hotels and hostels or possible resistance to insecticides.
Lifecycle of a Bed Bug
The lifecycle starts with an egg, where a bed bug nymph hatches out and passes through 5 stages before reaching maturity. The speed at which the insects develop is dependent on temperature, and the availability of food. Under optimum conditions they can develop from egg to adult in 3 weeks. In severe infestations thousands of Bedbugs can be present.
Adult bed bugs are oval, wingless insects, which are about 5-7 mm long. They are flattened dorsoventrally, and this feature allows them to hide in narrow spaces such as into cracks and crevices. When unfed, they are pale yellow or brownish in colour, but after a full blood meal, they take a darker uniform ‘mahogany’ brown colour.
Bed bugs have piercing mouthparts formed into a proboscis, used to pierce the host’s skin. They have three pairs of legs that are slender but well-developed and with efficient tarsal claws for clinging on to the host during feeding and spreading by passive means.
Up to 500 eggs can be produced by one female, which are then glued into cracks and crevices with cement like substance. The eggs will hatch in 6-10 days if it is warm, but will not hatch at all if the temperature is below 13°C.
