Signs of bed bugs in a London flat

Bed bugs are shy. They hide during the day and come out to feed while you sleep, so it is common to have them for weeks before seeing one. Most people notice the evidence they leave behind first. Here is what that evidence looks like, and where to look for it in a typical London flat or house.

The five signs to look for

1. Dark spots and stains

This is the most reliable sign. The British Pest Control Association describes clusters of reddish-brown or ink-dot-like spots about 1mm wide. They are droppings, made of digested blood, and they often bleed slightly into the fabric like a felt-tip dot.

You find them where bed bugs rest: along the piping and seams of the mattress, on the corners of the bed base, in the joints of the frame and on the back of the headboard.

2. Small blood smears

Rusty or red smears on the sheets, pillowcases or headboard happen when a bug that has just fed gets crushed as you turn over. The NHS lists blood spots on bedding as one of the main signs.

3. Shed skins and eggs

Young bed bugs shed their skins five times as they grow. The skins look like pale, empty, see-through copies of the bug. Eggs are tiny, whitish and sticky, about the size of a pinhead, and are usually tucked into seams and cracks. You need a torch and a close look to spot them.

4. The bugs

Adults are flat, oval and reddish-brown, roughly the size of an apple pip. After feeding they look fatter, longer and darker red. Younger ones are smaller and paler, almost straw-coloured until they feed.

If you find one, catch it on clear sticky tape or in a sealed sandwich bag. A specialist can identify it, and it saves an argument with a landlord later.

5. Bites

Bed bug bites are raised, itchy and often in a line or a small group. The NHS says they tend to be on areas exposed in bed, such as the face, neck, arms and hands. On white skin they usually look red or pink; on black or brown skin they may look brown, red or purple and be harder to see.

Bites alone are not proof. Fleas, mosquitoes, mites and skin conditions can look similar, and some people do not react to bed bug bites at all. Two people can share a bed and only one gets bitten. Look for the other signs before paying for treatment.

Where to look

Start with the bed and work outwards. Bed bugs like to stay within a couple of metres of where people sleep.

1. The mattress. Lift it and check the seams, piping, labels and the underside, especially the corners at the head end.
2. The bed base and frame. Divan bases have a fabric underside where bugs gather. Wooden and metal frames have joints, screw holes and slats.
3. The headboard. Upholstered headboards are a favourite. Check the back, where it meets the wall.
4. Beside the bed. Bedside tables, the skirting board behind the bed, the edges of the carpet, and plug sockets.
5. The sofa. If anyone sleeps on it, or has fallen asleep on it, check the seams and under the cushions.
6. Further out. Curtain tops, picture frames, loose wallpaper and cracks in plaster, in a bad infestation.

A bright torch and an old bank card help: run the card along seams to push out anything hiding.

Signs specific to London flats

In a block or converted house, also think about the building:

• Spots near a shared wall. If the evidence is concentrated on the side of the bed against a party wall, the bugs may be coming from next door.
• A neighbour’s mattress outside. A mattress left in a communal area or by the bins is sometimes a sign that another flat is being treated.
• Bites after a neighbour’s treatment. Treatment in one flat can push bed bugs into the next.

If any of these apply, tell your landlord, managing agent or housing officer, not only a pest firm.

Things that look like bed bugs but are not

• Carpet beetle larvae. Small, hairy and stripy, found in carpets and wardrobes. They do not bite, but their hairs can irritate skin.
• Fleas. Tiny and dark, they jump. Bites are usually around the ankles and lower legs, and there is often a pet involved.
• Booklice and spider beetles. Common in older London buildings, harmless, and they do not feed on blood.

If you are unsure, a photo taken close up in good light is often enough for a specialist to tell you.

What to do when you find signs

Do not panic, and do not reach for a spray. Shop-bought sprays and foggers usually scatter bed bugs into new rooms. Instead:

• Keep sleeping in your own bed. Moving to the sofa spreads them.
• Run the bedding and clothes from that room through a 60°C wash and a hot dryer cycle of half an hour or more, in line with NHS advice.
• Seal items you cannot wash in a plastic bag and leave them in the same room.
• If you rent, tell your landlord in writing straight away.
• Book an inspection or a treatment. NHS guidance is plain that home methods seldom clear them.

For bites that are very itchy, swollen or painful, a pharmacist can advise. See a GP if the swelling spreads or you feel unwell.

Getting it confirmed

A specialist inspection in London usually costs £60 to £150 and gives you a straight answer, which matters if you rent or are about to pay for treatment. See bed bug inspections in London, or check the London price calculator for what treatment is likely to cost.