Bed bugs: how to spot them, and what to do about them

Bed bugs have lived alongside people for thousands of years, and they are no reflection on how clean a home is. They travel in luggage, clothing and second-hand furniture, hide within a few metres of where people sleep, and come out at night to feed. Here is how to recognise them, and why they need a methodical approach to clear.

01What bed bugs look like

• Adults are about 5mm long, roughly the size and shape of an apple seed: oval, flat and brown, turning redder and more swollen after a feed.
• Young bed bugs (nymphs) are smaller and paler, almost translucent before they feed.
• Eggs are about 1mm long, white and stuck into cracks and seams.

Bed bugs cannot fly or jump, but they crawl quickly over walls, floors, ceilings and furniture. They are drawn to the warmth and carbon dioxide of a sleeping person, and they can survive for months between feeds, which is why an empty room is not a cure.

02Signs of bed bugs

• Dark spots. Small black or dark brown marks on mattress seams, the bed frame, the headboard and nearby furniture. These are droppings, and they smear like ink if you wipe them with a damp cloth.
• Blood marks. Small rust-coloured smears on sheets and pillowcases, often from a bug squashed after feeding.
• Shed skins and live bugs tucked into seams, joints, screw holes, behind the headboard and along skirting boards.
• A sweet, musty smell in a heavy infestation.
• Bites. Itchy red bumps, often in a line or cluster, on skin left uncovered at night such as the face, neck, arms and shoulders. On darker skin they can look purple rather than red.

Bites alone are not proof. Many people do not react to bed bug bites at all, and the bites are easily confused with flea bites, mosquito bites and skin conditions. Flea bites tend to be lower down, around the ankles and lower legs. If you are getting bitten, look for the physical signs above before drawing conclusions.

03Are bed bugs harmful?

Bed bugs are not known to spread disease to people, but they are still a health problem. Bites can be very itchy and swollen, and scratching can lead to skin infections. A pharmacist can advise on creams and antihistamines to ease the itching. In rare cases a person has a severe allergic reaction: if anyone has difficulty breathing, swelling of the face or throat, or feels faint, call 999.

The effect on sleep and peace of mind is often the hardest part. Lying awake expecting to be bitten causes real stress and anxiety, and it is one of the main reasons to deal with bed bugs promptly.

04Why bed bugs are hard to clear

• They hide well. Bed bugs fit into cracks the thickness of a credit card, so an infestation is often bigger than it looks.
• Eggs survive. One missed batch of eggs is enough to restart the problem, so treatment has to reach every stage of the life cycle.
• Resistance. Many bed bug populations have become resistant to insecticides that once worked well, including those in many products sold to the public.
• DIY spreads them. Sprays and foggers often drive bed bugs out of the bed and into skirting boards, sockets and neighbouring rooms, which makes the job larger.

05What to do if you think you have them

• Do not start moving furniture and belongings between rooms, and try not to sleep in a different room, as the bed bugs will follow and spread.
• Do not throw out the mattress straight away. Carrying an infested mattress through the house can scatter bugs along the way, and a new bed will be infested again if the room is not treated.
• Wash bedding and clothing from the affected room at 60°C, or tumble dry on a hot setting for at least 30 minutes. Items that cannot be washed can be sealed in a bag and put in the freezer for at least three days.
• Vacuum the bed, seams and floor around it, and empty the vacuum into a sealed bag in an outside bin.
• Get it confirmed. A photo of what you have found, or a sample stuck to clear tape, lets us tell you whether it is bed bugs.

06What treatment involves

Treatment starts with a thorough inspection to find out how far the infestation has spread. The rooms are then treated with professional insecticides, heat, or a combination, applied to the bed, furniture, seams, cracks and skirting where bed bugs shelter. Because eggs are protected, a follow-up visit is normally needed to deal with bugs that hatch afterwards. We will tell you how to prepare the room beforehand, which makes a real difference to the result. Mattress encasements can help afterwards by leaving bed bugs nowhere to hide on the mattress.

07Preventing bed bugs

• Check hotel and holiday beds before you unpack. Our guide to avoiding bed bugs after a holiday covers this step by step.
• Inspect second-hand beds, sofas and furniture closely before bringing them home, paying attention to seams, joints and screw holes.
• Keep clutter down around beds, so there are fewer places to hide and anything unusual is easier to spot.
• Check the bed and headboard now and then, especially after guests have stayed or you have been away.